Text preview for : Portege 610CT, 620CT Service Manual.pdf part of Toshiba Portege 610CT 620CT Portegè 610CT service manual (start at page72) with Portegè 620CT service maintenance manual addendum. Complete with troubleshooting, block descriptions, testing, substitution instructions, detailed views, BIOS rewrite procedure
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TOSHIBA
620CT
Addendum to the 610CT Maintenance Manual
PN: 620-9400
CARM-B960289-B00
Copyright
©1996 by Toshiba Corporation. All rights reserved. Under the copyright laws, this manual cannot be
reproduced in any form without the prior written permission of Toshiba. No patent liability is assumed with
respect to the use of the information contained herein.
PORTÉGÉ 620CT, Addendum to the 610 CT Maintenance Manual
First edition November 1996
Disclaimer
The information contained in this manual is subject to change without notice.
Toshiba Corporation and Toshiba America Information Systems, Inc., assume no liability for damages
incurred directly or indirectly from errors, omissions, or discrepancies in connection with the furnishing,
performance, or use of this material.
Trademarks
IBM, PC/AT, PS/2, OS/2 and VGA are trademarks of IBM Corporation.
MS-DOS and Windows are registered trademarks of Microsoft Corporation.
Intel and Pentium are registered trademarks of Intel Corporation.
Lotus is a registered trademark of Lotus Development Corporation.
Novell and NetWare are registered trademarks of Novell, Inc.
UNIX is a registered trademark of X/Open Company Ltd.
Sound Blaster and Pro are trademarks of Creative Technology Ltd.
Centronics is a registered trademark of Centronics Data Computer Corporation.
All other properties are trademarks or registered trademarks of their respective holders.
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i 620 Maintenance Manual Addendum
About this Addendum
This addendum is a supplement to the Toshiba 610CT Maintenance Manual. The information
contained in this publication covers features, field replaceable units, and disassembly/
reassembly of the Toshiba 620CT computer. For information on troubleshooting, tests and
diagnostics, board layout, pin assignments, etc., please refer to the 610CT Maintenance
Manual.
SAFETY PRECAUTIONS
Four types of messages are used in this manual to bring important
information to your attention. Each of these messages will be italicized
and identified as shown below.
DANGER: "Danger" indicates the existence of a hazard that could result in death
or serious bodily injury if the safety instruction is not observed.
WARNING: "Warning" indicates the existence of a hazard that could result in
bodily injury if the safety instruction is not observed.
CAUTION: "Caution" indicates the existence of a hazard that could result in
property damage if the safety instruction is not observed.
NOTE: A "Note" contains general information that relates to safe maintenance
services.
Improper repair of the computer may result in safety hazards. Toshiba
requires service technicians and authorized dealers or service providers
to ensure the following safety precautions are strictly adhered to.
u Be sure to fasten screws securely with the right screwdriver. If a
screw is not fully fastened, it could come loose, creating a danger
of a short circuit, which could cause overheating, smoke or fire.
u If you replace the battery pack, RTC battery or backup battery, be
sure to use only the same model battery or an equivalent battery
recommended by Toshiba. Installation of the wrong battery can
cause the battery to explode.
620 Maintenance Manual Addendum i
Table of Contents
able
Chapter 1 Hardware Overview
1.1 Features ..................................................................................................................... 1-1
1.2 System Unit Block Diagram ..................................................................................... 1-4
1.3 3.5-inch External Floppy Disk Drive ........................................................................ 1-8
1.4 2.5-inch Hard Disk Drive .......................................................................................... 1-9
1.5 Keyboard ................................................................................................................. 1-10
1.6 TFT Color LCD ...................................................................................................... 1-11
1.7 Power Supply .......................................................................................................... 1-13
1.8 Batteries .................................................................................................................. 1-14
Chapter 2 Troubleshooting Procedures
See the 610CT Maintenance Manual
Chapter 3 Tests and Diagnostics
See the 610CT Maintenance Manual
Chapter 4 Replacement Procedures
4.1 General ...................................................................................................................... 4-1
4.2 The Battery Pack ...................................................................................................... 4-6
4.3 Memory Module ....................................................................................................... 4-8
4.4 PC Card .................................................................................................................. 4-11
4.5 Keyboard ................................................................................................................. 4-13
4.6 Hard Disk Drive (HDD) ......................................................................................... 4-16
4.7 Top Cover with Display Assembly.......................................................................... 4-18
4.8 RTC and Backup Batteries ..................................................................................... 4-21
4.9 Membrane Switch ................................................................................................... 4-23
4.10 Sound Board ........................................................................................................... 4-24
4.11 Power Supply Board ............................................................................................... 4-26
4.12 System Board .......................................................................................................... 4-28
4.13 LED Board and Speaker ......................................................................................... 4-30
4.14 Display Mask .......................................................................................................... 4-32
4.15 FL Inverter Board ................................................................................................... 4-34
4.16 TFT Color Display Module..................................................................................... 4-36
4.17 Fluorescent Lamp Unit (FL) ................................................................................... 4-38
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Appendices
Appendix A Handling the LCD Module*
Appendix B Board Layout*
Appendix C Pin Assignments*
Appendix D Keyboard Scan/Character Codes*
Appendix E Key Layouts*
Appendix F Wiring Diagrams*
Appendix G BIOS Rewrite Programs*
*See the 610CT Maintenance Manual
620 Maintenance Manual Addendum v
Chapter 1
Hardware Overv ew
Hard Overv ew
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Chapter 1 Contents
1.1 Features ..................................................................................................................... 1-1
1.2 System Unit Block Diagram ..................................................................................... 1-4
1.3 3.5-inch External Floppy Disk Drive (FDD) ............................................................. 1-8
1.4 2.5-inch Hard Disk Drive (HDD) ............................................................................. 1-9
1.5 Keyboard ................................................................................................................. 1-10
1.6 TFT Color LCD ...................................................................................................... 1-11
1.6.1 LCD Module ............................................................................................... 1-11
1.6.2 Fluorescent Lamp (FL) Inverter Board....................................................... 1-12
1.7 Power Supply .......................................................................................................... 1-13
1.8 Batteries .................................................................................................................. 1-14
1.8.1 Main Battery ............................................................................................... 1-14
1.8.2 Battery Charging Control............................................................................ 1-15
1.8.3 Backup Battery ........................................................................................... 1-16
1.8.4 RTC Battery ................................................................................................ 1-16
Figures
Figure 1-1 Computer ...................................................................................................... 1-3
Figure 1-2 System unit configuration ............................................................................. 1-3
Figure 1-3 System board block diagram ......................................................................... 1-4
Figure 1-4 3.5-inch external FDD................................................................................... 1-8
Figure 1-5 2.5-inch HDD................................................................................................ 1-9
Figure 1-6 Keyboard ..................................................................................................... 1-10
Figure 1-7 TFT color LCD ........................................................................................... 1-11
Tables
Table 1-1 3.5-inch external FDD specifications ............................................................ 1-8
Table 1-2 2.5-inch HDD specifications ......................................................................... 1-9
Table 1-3 TFT color LCD specifications .................................................................... 1-11
Table 1-4 FL inverter board specifications .................................................................. 1-12
Table 1-5 Power supply board output rating............................................................... 1-13
Table 1-6 Battery specifications .................................................................................. 1-14
Table 1-7 Time required for quick charges ................................................................. 1-15
Table 1-8 Backup battery charging/data preservation time ......................................... 1-16
Table 1-9 RTC battery charging/data preservation time ............................................. 1-16
620 Maintenance Manual Addendum 1ii
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1.1 Features
The 620CT uses extensive Large Scale Integration (LSI), and Complementary Metal-Oxide
Semiconductor (CMOS) technology to provide minimum size and weight, low power usage,
and high reliability. This computer incorporates the following features and benefits:
u Microprocessor
Uses an Intel Pentium processor 100 MHz with VRT (Voltage Reduction Technol-
ogy) that operates at 2.9/3.3 volts. The math co-processor and 16 KB cache memory
are integrated into Pentium.
u Disk storage
An internal 1.3 billion byte (1.26 GB) Hard Disk Drive (HDD). An external 3.5-inch
Floppy Disk Drive (FDD) supports 2HD (1.44 MB) floppy disks and 2DD (720 KB)
floppy disks.
u Memory
Standard with 8 MB of EDO (Extend Data Out) DRAM. This includes 640 KB of
conventional memory and 7360 KB of extended memory, which can be utilized as
expanded memory compatible with the Lotus/Intel/Microsoft Expanded Memory
Specification (LIM-EMS).
u LCD
A 10.4-inch TFT (Thin Film Transistor) color LCD 800 x 600 pixels. The built-in
display controller supports full color capability and up to 1024 x 768 resolution on an
external CRT.
u Keyboard
An-easy-to-use 82/84-key keyboard provides a numeric keypad overlay for fast nu-
meric data entry or for cursor and page control. The keyboard supports software that
uses a 101- or 102-key enhanced keyboard.
u Batteries
Three different batteries: a Lithium-Ion main battery, a backup battery (for memory
backup), and an RTC battery (Real Time Clock).
u Exp. memory slot
An optional 8, 16, or 32 MB memory module can be installed in the memory slot.
620 Maintenance Manual Addendum 1-1
u Parallel port
Can be used to connect a Centronics compatible printer or other parallel device. The
port supports ECP (Extended Capabilities Port) conforming to IEEE·1284.
u Serial port
The serial controller is 16550UART compatible. This standard, 9-pin serial port can be
used to connect such serial devices as a serial printer, serial mouse, or external mo-
dem.
u Port replicator port
A port replicator port which enables connection of a port replicator or external moni-
tor adapter. The port replicator allows connection of a PS/2 mouse, PS/2 keyboard,
external monitor, printer, DC IN, serial I/O, and an external FDD. The display adapter
allows connection of an external monitor.
u External FDD port
The external FDD port lets you connect an external FDD.
u PC card slot
A PC card slot supports up to two Personal Computer Memory Card International
Association (PCMCIA) release 2.0 standard cards. The upper and lower slots can each
accommodate one Type II (5.0 mm) card. The lower slot can accommodate one Type
III (10.5 mm) card when the upper slot is empty.
u AccuPoint
A pointer control stick, located in the center of the keyboard, provides convenient
control of the cursor without requiring desk space for a mouse.
u Sound System
Sound Blaster Pro compatible sound system to record sound and play it back with a
built-in microphone and speaker. The sound system provides a volume control dial,
headphone jack, and microphone jack.
1-2 620 Maintenance Manual Addendum
The computer is shown in Figure 1-1.
Figure 1-1 Computer
The system configuration is shown in Figure 1-2.
Figure 1-2 System unit configuration
620 Maintenance Manual Addendum 1-3
1.2 System Unit Block Diagram
Block Diagram
Figure 1-3 is a block diagram of the system unit.
Figure 1-3 System board block diagram
1-4 620 Maintenance Manual Addendum
The system board is composed of the following major components:
u One Intel Pentium-100 MHz with VRT 64-bit microprocessor
Intel Pentium processor operates at 100 MHz and 2.9 volts and 3.3 volts. It incorpo-
rates a math coprocessor and a 16KB cache.
u Standard RAM
8 MB, four 1Mx16-bit EDO DRAM chips
3.3 volt operation
No parity bit
Access time 60 ns
Data transfer is 64-bit width
u BIOS ROM (Flash EEPROM)
128 KB (One 128Kx8-bit chip) memory
64 KB in the ROM are used for system BIOS
32 KB in the ROM are used for VGA BIOS
32 KB in the ROM are reserved
Access time 150 ns
Data transfer is 8-bit width
u Video RAM
1 MB (Two 256Kx16-bit DRAMs)
5 volt operation
u Optional memory
One expansion memory slot is available for 8, 16, and 32 MB memory modules,
which may consist of 1 MBx16-bit EDO DRAM chips. Total maximum
memory size is 40 MB (if a 32 MB memory module is installed).
3.3 volt operation
No parity bit
Access time 60 ns
Data transfer is 64-bit width
u One super integration (SI-T6W23A)
Consists of the following components:
Two DMACs 82C37 equivalent
Two PICs 82C59 equivalent
Two SIOs 16550 equivalent (One SIO is not used)
One PIT 82C54 equivalent
One FDC TC8565 equivalent
One VFO TC8568 equivalent
One I/O port decode
One SIO port control
One printer port control supported ECP
One FDD control
One speaker control
One power communication control
620 Maintenance Manual Addendum 1-5
u System Controller Gate Array (SCPCNT-GA)
This gate array has the following functions:
CPU control
SMI control
CPU clock control
Memory control
64-bit bus memory control
32-bit bus memory control
Bus control
64-bit data bus <==> 32-bit data bus
32-bit local bus control
Address latch control
I/O register control
Processing speed control
u ISA Bus Controller Gate Array (SISCNT-GA)
This gate array has the following functions:
Bus control
32-bit data bus <==> 16-bit data bus
ISA bus interface control
ISA bus access control
DMAC control
DMA address generation
I/O control
Memory control
ISA bus interface control
Refresh address generation
I/O register control
Suspend/Resume sequence
u PC Card Controller Gate Array
This gate array has the following functions:
PCMCIA memory card control
PCMCIA I/O card control
u I/O Controller Gate Array
This gate array has the following functions:
Internal Communication control
KBC, main CPU communication register file
KBC interrupt control
Others
KBC communication control. Contrast adjust,
speaker volume adjust PWM control, Sound board
interface, BIOS-ROM interface, SMI control
u Video Controller
Chips & Technologies F65548 is used.
Controls internal TFT color LCD and external SVGA compatible CRT.
1-6 620 Maintenance Manual Addendum
u Keyboard Controller (KBC)
One M38802M4 chip is used.
This KBC includes the keyboard scan controller and keyboard interface controller.
The KBC controls the internal keyboard, external keyboard, AccuPoint, and PS/2
mouse.
u AccuPoint Controller (IPSC)
One U43SC10 chip is used.
Provides simultaneous control of both the AccuPoint and a PS/2 mouse.
u Real Time Clock (RTC)
One T9934 chip is used.
The T9934 has 128 bytes of memory. Fourteen bytes of memory are used for the
calendar and clock. The remaining 114 bytes are used for the system configuration
data.
620 Maintenance Manual Addendum 1-7
1.3 3.5-inch External Floppy Disk Drive (FDD)
3.5-inch Floppy
The 3.5-inch external FDD is a thin, high-performance reliable drive that supports 720-KB
(formatted) 2DD and 1.44-MB (formatted) 2HD 3.5-inch floppy disks.
The FDD is shown in Figure 1-4.
Figure 1-4 3.5-inch external FDD
The specifications for the FDD are listed in Table 1-1.
Table 1-1 3.5-inch external FDD specifications
Item 2-MB mode 1-MB mode
Storage capacity (KB)
Unformatted 2,000 1,000
Formatted 1,440 720
Number of heads 2 2
Number of cylinders 80 80
Access time (ms)
Track to track 3 3
Average 181 181
Head settling time 15 15
Recording track density (tpi) 135 135
Data transfer rate (Kbps) 500 250
Rotation speed (rpm) 300 300
Recording method Modified Frequency Modulation (MFM)
1-8 620 Maintenance Manual Addendum
1.4 2.5-inch Hard Disk Drive (HDD)
2.5-inch Hard
The HDD is a random access non-volatile storage device. It has a non-removable 1.3 billion
byte (1.26GB), 2.5-inch magnetic disk and mini-winchester type magnetic heads.
The HDD is shown in Figure 1-5.
Figure 1-5 2.5-inch HDD
Specifications for the HDD are listed in Table 1-2.
Table 1-2 2.5-inch HDD specifications
Items (MK1301MAV)
Storage capacity (GB)
Formatted 1.26
Number of disks 3
Data heads 16
Data surfaces 6
Bytes per sector 512
Rotation speed (rpm) 4200
Recording method 8-9 RLL
620 Maintenance Manual Addendum 1-9
1.5 Keyboard
yboard
The 82-(USA) or 84-(European) key keyboard is mounted on the system unit. The keyboard
is connected to the keyboard controller on the system board through a 25-pin flat cable. The
pointer control stick, located in the center of the keyboard, provides convenient control of the
cursor without requiring desk space for a mouse. The keyboard is shown in Figure 1-6.
See Appendix E of the Portégé 610CT Maintenance Manual for optional keyboard configura-
tions.
Figure 1-6 Keyboard
1-10 620 Maintenance Manual Addendum
1.6 TFT Color LCD
The TFT Color Liquid Crystal Display (LCD) contains an LCD module, a Fluorescent Lamp
(FL), and an FL inverter board.
1.6.1 LCD Module
The TFT color LCD supports 800 x 600 pixels with an internal display controller and 256K
colors for graphics and characters. This controller includes the functions of Video Graphics
Array (VGA) and Super VGA (SVGA) for display.
The LCD receives 9-bit data signals, data enable signals, and a shift clock for data transmis-
sion. All signals are CMOS-level compatible.
The TFT LCD is shown in Figure 1-7.
Figure 1-7 TFT color LCD
The specifications for the LCD are listed in Table 1-3.
Table 1-3 TFT color LCD specifications
Item Specifications
Number of dots (dots) 800 x 600
Dot pitch (mm) 0.264 x 0.264
Display area (mm) 211.2 x 158.4
Contrast 100
FL current (mA) 4.6/4.0/2.8/2.4*
(Bright/Semi-bright)
*NOTE: The FL currents at power on are:
Bright Semi-bright
AC adapter connected 4.6 mA 2.8 mA
AC adapter not connected 4.0 mA 2.4 mA
(The settings at power on do not change even if the AC adapter connection
changes.)
620 Maintenance Manual Addendum 1-11
1.6.2 Fluorescent Lamp (FL) Inverter Board
The FL inverter board supplies high frequency current to light the LCD Fluorescent Lamp.
The specifications for the FL inverter are listed in Table 1-4.
Table 1-4 FL inverter board specifications
Item Specifications
Input Voltage (VDC) 4 to 5.5
Power (W) 4.8
Output Voltage (Vrms) 1,100
Current (mA) 4.6/4.0/2.8/2.4*
(Bright/Semi-bright)
*NOTE: The FL currents at power on are:
Bright Semi-bright
AC adapter connected 4.6 mA 2.8 mA
AC adapter not connected 4.0 mA 2.4 mA
(The settings at power on do not change even if the AC adapter connection
changes.)
1-12 620 Maintenance Manual Addendum
1.7 Power Supply
Supply
The power supply provides five kinds of voltages to the system board. The power supply has
one microprocessor that operates at 500 KHz and contains the following functions:
1. Determines if the AC adapter or battery is connected to the computer.
2. Controls the LED icon and speaker.
3. Determines when the battery is fully charged.
4. Controls power on/off.
5. Searches for low/high voltage at power I/O areas.
6. Calculates the remaining battery capacity.
7. Displays error status on the LED.
8. Controls boot mode and resume mode reset.
9. Controls power to the LCD/FL based on the LCD panel sensor.
10. Controls intensity of the backlight FL.
11. Conserves data in the system buffer when power is off.
12. Controls the main battery's power flow.
13. Controls alarm beeps for power supply errors.
The power supply output rating is specified in Table 1-5.
Table 1-5 Power supply output rating
DC Regulation
Use for Name voltage tolerance
(V) (%)
System logic, FDD, HDD, Display VCC +5 ±5
RS-232C P+12V +12 ±5
RAM B3V +3.3 ±5
VGA,I/O B5V +5 ±5
CPU CPUV, B3V +2.9, +3.3 ±5
620 Maintenance Manual Addendum 1-13
1.8 Batteries
The computer has three types of batteries:
u Main battery pack
u Backup battery
u Real Time Clock (RTC) battery
Battery specifications are listed in Table 1-6.
Table 1-6 Battery specifications
Battery name Material Output voltage Capacity
Main battery Lithium-Ion 10.8 V 4,000 mAH
Backup battery Nickel Metal Hydride 6.0 V 110 mAH
RTC battery Nickel Metal Hydride 3.6 V 30 mAH
1.8.1 Main Battery
The removable main battery pack is the computer's main power source when the AC adapter
is not attached. The main battery recharges the backup battery when the system power is on.
The backup and main battery maintain the state of the computer when you enable
AutoResume.
u Battery Indicator
The battery indicator is located on the front of the computer. The indicator shows the
status of the removable battery pack, power supply, and AC adapter.
The status of each can be determined by color:
Orange The battery is being charged. (AC adapter is attached.)
Green The battery is fully charged. (AC adapter is attached.)
No light The AC adapter is disconnected from the computer. The AC adapter is
connected, but it cannot charge the battery for one of the following reasons:
· The battery is extremely hot. Allow the computer and the battery to
reach room temperature before attempting to charge the battery.
· The battery is almost fully discharged. The battery will not begin
charging immediately in this state, it will begin charging a few minutes
after the AC adapter is connected.
· The AC adapter is not receiving power.
1-14 620 Maintenance Manual Addendum
1.8.2 Battery Charging Control
Battery charging is controlled by a power supply microprocessor that is mounted on the
power supply. The microprocessor controls whether the charge is on or off and detects a full
charge when the AC adapter and battery are attached to the computer. The system charges
the battery using quick charge or trickle charge.
u Quick Battery Charge
When the AC adapter is attached, there are two types of charge: quick charge when
the system is powered off and trickle charge when the system is powered on.
Table 1-7 Time required for quick charges
Charging time
Quick charge About 4 hours
(power off)
Trickle charge About 5 to 8 hours
(power on)
If one of the following occurs, the battery quick-charge process stops.
1. The battery becomes fully charged.
2. The AC adapter or battery is removed.
3. The battery or AC adapter output voltage is abnormal.
4. The charge current is abnormal.
u Trickle Battery Charge
When the main battery is fully charged and the AC adapter is attached, the power
supply microprocessor automatically changes quick charge to trickle charge.
620 Maintenance Manual Addendum 1-15
1.8.3 Backup Battery
The backup battery maintains data for resume. The power source used to back-up the resume
data is determined according to the following priority:
AC adapter > Main battery > Backup battery
The backup battery is charged by the main battery or AC adapter when the system is powered
on. Table 1-8 shows the charging time and data preservation period of the backup battery.
Table 1-8 Backup battery charging/data preservation time
Time
Charging Time Power On 40 H
Power Off (with AC Adapter) 40 H
Power Off (Without AC Adapter) Doesn't charge
Data preservation period (full charge) 1.5 H
1.8.4 RTC Battery
The RTC battery provides power to keep the current date, time, and other setup information
in memory while the computer is turned off. Table 1-9 shows the charging time and data
preservation period of the RTC battery.
Table 1-9 RTC battery charging/data preservation time
Time
Charging Time Power On 70 H
Power Off Dosen't charge
Data preservation period (full charge) 1 month
1-16 620 Maintenance Manual Addendum
Chapter 4
Replacement Procedures
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Chapter 4 Contents
4.1 General ...................................................................................................................... 4-1
Safety Precautions..................................................................................................... 4-2
Before You Begin ..................................................................................................... 4-3
Disassembly Procedures ............................................................................................ 4-4
Assembly Procedures ................................................................................................ 4-4
Tools and Equipment ................................................................................................ 4-5
Screw Tightening Torque ......................................................................................... 4-5
4.2 The Battery Pack ...................................................................................................... 4-6
Removing the Battery Pack ...................................................................................... 4-6
Installing the Battery Pack ........................................................................................ 4-7
4.3 Memory Module ....................................................................................................... 4-8
Removing the Memory Module ................................................................................ 4-8
Installing the Memory Module ................................................................................ 4-10
4.4 PC Card .................................................................................................................. 4-11
Removing the PC Card ........................................................................................... 4-11
Installing the PC Card ............................................................................................. 4-12
4.5 Keyboard ................................................................................................................. 4-13
Removing the Keyboard ......................................................................................... 4-13
Installing the Keyboard ........................................................................................... 4-15
4.6 Hard Disk Drive (HDD) ......................................................................................... 4-16
Removing the HDD ................................................................................................ 4-16
Installing the HDD .................................................................................................. 4-17
4.7 Top Cover and Display Assembly ........................................................................... 4-18
Removing the Top Cover and Display Assembly .................................................... 4-18
Installing the Top Cover and Display Assembly ..................................................... 4-20
4.8 RTC and Backup Batteries ..................................................................................... 4-21
Removing the RTC and Backup Batteries .............................................................. 4-21
620 Maintenance Manual Addendum 4ii
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Installing the RTC and Backup Batteries ................................................................ 4-22
4.9 Membrane Switch ................................................................................................... 4-23
Removing the Membrane Switch ............................................................................ 4-23
Installing the Membrane Switch .............................................................................. 4-23
4.10 Sound Board ........................................................................................................... 4-24
Removing the Sound Board .................................................................................... 4-24
Installing the Sound Board...................................................................................... 4-25
4.11 Power Supply Board ............................................................................................... 4-26
Removing the Power Supply Board ........................................................................ 4-26
Installing the Power Supply Board ......................................................................... 4-27
4.12 System Board .......................................................................................................... 4-28
Removing the System Board................................................................................... 4-28
Installing the System Board .................................................................................... 4-29
4.13 LED Board and Speaker ......................................................................................... 4-30
Removing the LED Board and Speaker .................................................................. 4-30
Installing the LED Board and Speaker ................................................................... 4-31
4.14 Display Mask .......................................................................................................... 4-32
Removing the Display Mask ................................................................................... 4-32
Installing the Display Mask ..................................................................................... 4-33
4.15 FL Inverter Board ................................................................................................... 4-34
Removing the FL Inverter Board ............................................................................ 4-34
Installing the FL Inverter Board ............................................................................. 4-35
4.16 TFT Color Display Module..................................................................................... 4-36
Removing the TFT Color Display Module ............................................................. 4-36
Installing the TFT Color Display Module ............................................................... 4-37
4.17 Fluorescent Lamp Unit (FL) ................................................................................... 4-38
Removing the FL Unit ............................................................................................ 4-38
Installing the FL Unit .............................................................................................. 4-39
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4.18 Microphone ............................................................................................................. 4-40
Removing the Microphone...................................................................................... 4-40
Installing the Microphone ....................................................................................... 4-40
4.19 Display Cable .......................................................................................................... 4-41
Removing the Display Cable ................................................................................... 4-41
Installing the Display Cable ..................................................................................... 4-41
Figures
Figure 4-1 Unlocking the battery pack ........................................................................... 4-6
Figure 4-2 Lifting out the battery pack ........................................................................... 4-6
Figure 4-3 Installing the battery pack ............................................................................. 4-7
Figure 4-4 Removing the memory module socket cover ................................................ 4-8
Figure 4-5 Removing the memory module ..................................................................... 4-9
Figure 4-6 Inserting the memory module ..................................................................... 4-10
Figure 4-7 Removing the PC card ................................................................................ 4-11
Figure 4-8 Installing the PC card .................................................................................. 4-12
Figure 4-9 Releasing the keyboard cover ..................................................................... 4-13
Figure 4-10 Removing the keyboard screw .................................................................... 4-14
Figure 4-11 Removing the keyboard .............................................................................. 4-14
Figure 4-12 Removing the keyboard cable ..................................................................... 4-15
Figure 4-13 Removing the HDD with bracket ............................................................... 4-16
Figure 4-14 Removing the HDD .................................................................................... 4-17
Figure 4-15 Removing the bottom cover screws ............................................................ 4-18
Figure 4-16 Releasing the top cover latches ................................................................... 4-19
Figure 4-17 Separating the top cover and display assembly ........................................... 4-19
Figure 4-18 Removing the RTC and backup batteries.................................................... 4-21
Figure 4-19 Removing the membrane switch ................................................................. 4-23
Figure 4-20 Removing the sound board ......................................................................... 4-24
Figure 4-21 Removing the power supply board ............................................................. 4-26
Figure 4-22 Removing the system board ........................................................................ 4-28
Figure 4-23 Removing the LED board and speaker assembly ........................................ 4-30
Figure 4-24 Removing the LED board ........................................................................... 4-30
Figure 4-25 Removing the seals and screws ................................................................... 4-32
Figure 4-26 Removing the display mask ......................................................................... 4-33
620 Maintenance Manual Addendum 4v
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Figure 4-27 Removing the FL inverter board ................................................................. 4-34
Figure 4-28 Removing the display module screws ......................................................... 4-36
Figure 4-29 Removing the LCD ..................................................................................... 4-37
Figure 4-30 Removing the FL unit screws ..................................................................... 4-38
Figure 4-31 Removing the FL unit ................................................................................. 4-39
Figure 4-32 Removing the FL ........................................................................................ 4-39
Figure 4-33 Removing the microphone .......................................................................... 4-40
Figure 4-34 Removing the display cable ......................................................................... 4-41
4v
-i 620 Maintenance Manual Addendum
41
. General
This section explains how to disassemble the computer and replace Field Replaceable Units
(FRUs). It may not be necessary to remove all the FRUs in order to replace one. The chart
below is a guide to which FRUs need to be removed in order to remove others. Always start
by removing the battery pack, then follow the lines on the chart to determine which FRU you
must remove next in order to repair the one you think is causing the computer to operate
improperly.
u Battery Pack Display u FL Inverter Board
Mask u TFT Color Display
u Memory Module u FL
u PC Card
u Keyboard
u Hard Disk Drive
u Top Cover LED Board
u RTC and Backup Battery and Speaker
u Membrane Switch
u Sound Board
u Power Supply Board
u System Board
620 Maintenance Manual Addendum 4-1
Safety Precautions
Before you begin disassembly, read the following safety precautions and observe them
carefully as you work.
DANGER:
1. Always use the lithium ion battery pack or back-up battery that is
authorized by Toshiba or compatible with the unit. Since other
battery packs have different specifications, they may be incompatible
with the unit, and may burst or explode.
Do not heat or disassemble the battery pack, as leakage of alkaline
solution could result. Do not throw the battery pack into a fire, as
that could cause the battery pack to explode.
2. The power supply, FL inverter, and other components carry high
voltages. To avoid the risk of electric shock when you turn on the
power of a partially disassembled computer to check its operation, be
very careful not to touch connectors or components. Also, do not
disassemble individual components during first-level maintenance.
WARNING:
To avoid the risk of electric shock or other injury:
1. Always turn the power off and disconnect the AC power cord from the
power source.
2. Remove any metal jewelry or accessories such as necklaces, bracelets,
or rings. Batteries in the computer retain electrical charge so there is
danger of electrical shock even when the computer is disconnected
from an AC power source.
3. Never work with wet or damp hands.
4. The computer contains many sharp edges and corners, so be careful
not to injure yourself.
CAUTION:
To avoid damage to the computer:
1. When you change a component, be sure the replacement component
meets the required specifications. Never use foreign parts.
2. Be sure metal objects such as screws or paper clips do not fall into the
unit, they can cause short-circuit, fire, or other internal damage.
3. Be sure to replace screws with the same size as those removed. Make
sure all screws are securely fastened. Loose screws can cause short
circuits, resulting in heat, smoke, or fire.
4. Before lifting out an FRU or other component, make sure all cables to
the component have been disconnected.
5. If you use AC power, be sure to use the cable that came with the
computer or one recommended by Toshiba.
6. Make sure that all replacement components meet the specifications for
the computer and that all cables and connectors are securely fastened.
4-2 620 Maintenance Manual Addendum
Before You Begin
Look over the procedures in this section before you begin disassembling the computer.
Familiarize yourself with the disassembly and reassembly steps. Begin each procedure by
removing the AC power cord and the battery pack as instructed in section 4.2, Battery Pack:
1. Do not disassemble the computer unless it is operating abnormally.
2. Use only the correct and approved tools.
3. Make sure the working environment is free from the following elements whether
you are using or storing the computer:
u Dust and contaminates
u Static electricity
u Extreme heat, cold, and humidity
4. Make sure the FRU you are replacing is causing the abnormal operation by
performing the necessary diagnostics tests described in this manual.
5. Do not perform any operations that are not necessary and use only the described
procedures for disassembling and installing FRUs in the computer.
6. After removing parts from the computer, place them in a safe place away from the
computer so they will not be damaged and will not interfere with your work.
7. You will remove and replace many screws when you disassemble the computer.
When you remove screws, make sure they are placed in a safe place and identified
with the correct parts.
8. When assembling the computer, make sure you use the correct screws to secure
the various pieces in place. Screw sizes are listed in the corresponding figures.
9. The computer contains many sharp edges and corners, so be careful not to injure
yourself.
10. After you have replaced an FRU, make sure the computer is functioning properly
by performing the appropriate test on the FRU you have fixed or replaced.
620 Maintenance Manual Addendum 4-3
Disassembly Procedures
The computer has three basic types of cable connectors:
u Pressure Plate Connectors
u Normal Pin Connectors
u Flexible Cable Connectors
To disconnect a Pressure Plate connector, lift up the tabs on either side of the plastic pressure
plate and slide the cable out of the connector. To connect the cable to a Pressure Plate
connector, make sure the pressure plate is fully lifted and slide the cable into the connector.
Secure the cable in place by pushing the sides of the pressure plate down so the plate is flush
with the sides of the connector. Gently pull on the cable to make sure the cable is secure. If
you pull out the connector, connect it again making sure the connector's pressure plate is fully
lifted when you insert the cable.
Standard pin and flexible cable connectors are used with all other cables. These connectors
can be connected and disconnected by simply pulling them apart or pushing them together.
Assembly Procedures
After you have disassembled the computer and fixed or repaired the problem that was causing
the computer to operate abnormally, you will need to reassemble the computer.
While assembling the computer, keep the following points in mind:
u Take your time, making sure you follow the instructions closely. Most problems arise
when you hurry to assemble the computer.
u Make sure all cables and connectors are securely fastened.
u Before securing the FRU or other parts, make sure that no cables will be pinched by
screws or the FRU.
u Check that all latches are closed securely in place.
u Make sure all the correct screws are used to secure all FRUs. Using the wrong screw
can damage either the threads on the screw or the head of the screw and may prevent
proper seating of an FRU.
After installing an FRU in the computer confirm that the FRU and the computer are
functioning properly.
4-4 620 Maintenance Manual Addendum
Tools and Equipment
The use of ElectroStatic Discharge (ESD) equipment is very important to prevent or minimize
ESD event damage to the unit under repair. Proper use of these devices will increase the
success rate of your repairs and lower the cost for damaged or destroyed parts. The
following equipment is necessary to disassemble and reassemble the computer:
t One M2 Phillips screwdriver to remove and replace screws
t Tweezers, to lift out screws that you cannot grasp with your fingers
t ESD mats for the floor and the table you are working on
t An ESD wrist strap or heel grounder
t Anti-static carpeting or flooring
t Air ionizers in highly static sensitive areas
Screw Tightening Torque
When you fasten screws, be sure to follow the torque list below. Overtightening can damage
components and screws; undertightening can result in electrical shorts or other damage if
screws or components come loose.
t M2 0.22 N·m (2.2 kgf·cm)
t M2.5 0.36 N·m (3.5 kgf·cm)
t FDD 0.22 N·m (2.2 kgf·cm)
t HDD 0.3 N·m (3.1 kgf·cm) or less
620 Maintenance Manual Addendum 4-5
42
. The Battery Pack
Battery Pac
ack
Removing the Battery Pack
To remove the battery pack, follow the steps below and refer to Figures 4-1 and 4-2.
1. Turn off the power to the computer. Disconnect the AC adapter, power cord, and
all external cables connected to the computer.
2. Close the display if it is open.
3. Turn the computer upside down.
4. Slide the battery lock to free the battery release latch, then slide the battery
release latch to pop the battery pack out about one centimeter to the left.
Figure 4-1 Unlocking the battery pack
5. A slight gap will open between the right end of the battery pack and the computer.
Slip your fingers into the gap and pull the battery pack to the left until it stops
(about 1 cm or half an inch).
6. Grasp the left end of the battery pack and lift it up to remove it.
Figure 4-2 Lifting out the battery pack
4-6 620 Maintenance Manual Addendum
Installing the Battery Pack
To install the battery pack, follow the steps below and refer to Figures 4-3 back through 4-1.
WARNING: The battery is a lithium ion battery and can explode if not properly
replaced, used, handled, or disposed of. Use only batteries recommended by Toshiba
as replacements.
NOTE: Check the battery terminals before you install the battery. If they are dirty,
wipe them clean with a dry cloth.
1. Place the right end of the battery pack at the red line marked on an alignment
guide. The battery pack should seat level with the computer.
Figure 4-3 Installing the battery pack
2. Gently press down on the center of the battery pack and at the same time push it to
the right. When the battery is nearly seated, you will feel a slight resistance. Press
the battery in carefully until you feel it click into place, then lock the battery lock.
620 Maintenance Manual Addendum 4-7
43
. Memory Module
Memory
Removing the Memory Module
To remove the memory module from the computer, follow the steps below and refer to
Figures 4-4 and 4-5.
1. Turn off the power to the computer. Disconnect the AC adapter, power cord, and
all external cables connected to the computer.
2. Remove the battery pack as described in Section 4.2.
3. Turn the computer upside down.
4. Remove two M2x4 silver screws securing the memory module socket cover.
5. Slide your fingernail or a thin object under the cover and remove it.
Figure 4-4 Removing the memory module socket cover
4-8 620 Maintenance Manual Addendum
6. Remove two M2x4 silver screws securing the module to a brace at the center of
the module and set them aside.
7. Insert a thin object under the upper edge of the module and lift up to disengage the
connector, then grasp the module by the edges and remove it.
NOTE: Some memory modules have a plastic tab. If so, simply pull up on the
tab to disengage the connector.
Figure 4-5 Removing the memory module
620 Maintenance Manual Addendum 4-9
Installing the Memory Module
To install the memory module in the computer, follow the steps below and refer to Figures
4-6 back through 4-4.
1. Position the connector on the bottom of the module over the corresponding
connector on the computer (align the holes on the side of the module over the
screw holes on the brace). Place your fingers above the connector and press firmly
but gently to assure a solid connection. The module should be seated level.
Figure 4-6 Inserting the memory module
2. Secure the module to the brace with two M2x4 silver screws.
3. Lay the cover in place. Secure it with two M2x4 silver screws. If the memory
module has a plastic tab, fold it down first then place the cover.
4. When you turn the computer on, it should automatically recognize the total
memory capacity. Verify that the added memory is recognized.
5. Install the battery pack as described in Section 4.2.
4-10 620 Maintenance Manual Addendum
44
. PC Card
Card
Removing the PC Card
To remove the PC card from the computer, follow the steps below and refer to Figure 4-7.
1. Turn off the power to the computer. Disconnect the AC adapter, power cord, and
all external cables connected to the computer.
2. Remove the battery pack as described in Section 4.2.
3. Open the cover to the PC card slot.
4. Pull out the eject button for the card you want to remove and press the button.
The card will pop out slightly.
Figure 4-7 Removing the PC card
5. Grasp the PC card and pull it out.
620 Maintenance Manual Addendum 4-11
Installing the PC Card
To install the PC card in the computer, follow the steps below and refer to Figure 4-8:
1. Insert the PC card as shown in Figure 4-8. When the card is almost fully seated,
you will feel some resistance. Press gently to assure a firm connection, but do not
force the card into position.
Figure 4-8 Installing the PC card
2. When the card is fully seated, an eject button will pop out; the top button for the
top connector and the bottom button for the bottom connector.
3. Pull the eject button slightly and bend it to lock the card.
4. Close the cover.
5. Install the battery pack as described in Section 4.2.
4-12 620 Maintenance Manual Addendum
45
. K eyboard
yboard
Removing the keyboard
To remove the keyboard, follow the steps below and refer to Figures 4-9 to 4-12.
1. Turn off the power to the computer. Disconnect the AC adapter, power cord, and
all external cables connected to the computer.
2. Remove the battery pack, memory module, and PC card as described in Sections
4.2, 4.3, and 4.4.
3. Use a case separator to release 12 latches that secure the keyboard cover. Begin
with the latches at the front.
Figure 4-9 Releasing the keyboard cover
620 Maintenance Manual Addendum 4-13
4. Remove one M2x4 screw with washer in front of the keyboard.
Figure 4-10 Removing the keyboard screw
5. Insert a thin object between the keyboard and the top cover to lift up the
keyboard. Lift up slightly so the extensions at the back of the keyboard clear the
corresponding holes on the top cover. Do not remove the keyboard cable.
Figure 4-11 Removing the keyboard
4-14 620 Maintenance Manual Addendum
6. Disconnect the AccuPoint cable from PJ2 and the keyboard cable from PJ7.
Figure 4-12 Removing the keyboard cable
7. Lift out the keyboard.
Installing the keyboard
To install the keyboard, follow the steps below and refer to Figures 4-12 back through 4-9.
1. Connect the AccuPoint cable to PJ2 and the keyboard cable to PJ7. Make sure
the pressure plate connectors are secure.
2. Replace the keyboard. Fit the extensions on the back of the keyboard into the
corresponding holes on the top cover and lay the keyboard in place.
3. Secure one M2x4 screw with washer in front of the keyboard.
4. Seat the keyboard cover and press firmly to secure 12 latches.
5. Replace the PC card, memory module, and battery pack as described in Sections
4.4, 4.3, and 4.2.
620 Maintenance Manual Addendum 4-15
46
. Hard Disk Drive (HDD)
Hard
Removing the HDD
To remove the HDD, follow the steps below and refer to Figures 4-13 and 4-14.
1. Turn off the power to the computer. Disconnect the AC adapter, power cord,
and all external cables connected to the computer.
2. Remove the battery pack, memory module, PC card, and keyboard as de-
scribed in Sections 4.2 through 4.5.
3. Remove one M2x4 screw securing the HDD bracket.
4. Lift up on the plastic tab on the HDD bracket and lift up the HDD.
5. Carefully pull the HDD to disconnect it from the connector then remove it.
Figure 4-13 Removing the HDD with bracket
4-16 620 Maintenance Manual Addendum
6. Remove four M3x4 flat-head screws securing the bracket to the HDD and
remove the bracket.
Figure 4-14 Removin