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I888, Standard Electrical Repairs

Approved according to 1776-2/FEA 209 544

Trouble-shooting
instruction

I 888

Standard electrical repairs

4-00021-2/FEA 209 544/5.C
I888, Standard Electrical Repairs

Table of contents
1 Conditions .......................................................................................... 3
2 No serv or can´t place call. ............................................................... 6
3 Doesn´t start. ................................................................................... 10
4 Audio ................................................................................................ 15
5 Display fault .................................................................................... 21
6 Charging fault ................................................................................. 24
7 SIM fault (Insert card) ................................................................... 27
8 Keyboard ......................................................................................... 29
9 Illumination and buzzer. ................................................................ 33
10 RTC (Real Time Clock) .................................................................. 38
11 IRDA fault. ...................................................................................... 40
12 Component list ................................................................................. 42

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1 Conditions

1.1 Component classifications.
After each component, which fault can be verified by the troubel-shooting guides in
this folder, is the components classification written. The components are divided in
four classes, A,B,C and D. The classes are seperated depending on how much of the
phone´s prestanda that is affected by changing the component.
Class A and B:Changing the component doesn´t affect the prestanda that much,
you only have to do a test call toward a real network before you perform a function
test after replacing it.
Class C: The phone has to be calibrated at station level after changing the com-
ponent, since the components tolerances are so large it can affect the prestanda of
the phone.
Class D: It demands advanced equipment and calibration at board level and
because of that class D-components can´t be replaced.

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1.2 Abbreviations used in the trouble-shooting
instructions.
B: Crystal
C: Capacitor
D: Digital circuit
F: Overload protection
H: Buzzer, ligth diodes, pads to the display
J: Connection
L: Coil
N: Analouge circuit
R: Resistor
U: BALUN. Component that converts a balanced signal to a nonbalanced or the
opposit direction.
V: Transistor, diode
X: Antenna connection, contact point on the board.
Z: Filter

AGND: Ground to analouge signal
DCIO: Direct current through the system connector for charging the bat-
tery.
DCON: Logical signal from the processor that keeps the phone powered on
after releasing the On/Off-button.
GND: Ground
LED3K: Logical signal that activates the illumination.
ONSRQ: Voltage from the On/Off-button that power on the phone.
REGON: Logical signal that activates the regulator for the voltage.
RTC: Real time clock. The clock that shows the time.
SIMCONCLK: Signal from the processor that is used for communication to SIM,
clock.
SIMCONDAT: Signal from the processor that is used for communication to
SIM,data.
SIMCONRST: Signal from the processorn that is used for communication to
SIM,reset.
SIMVCC: Feed voltage to SIM.
SWDC: Switch VBATT
VANA: Voltage to the analouge part of the logical circuit (N800).

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VBATT: Voltage of the battery.
VDIG: Voltage to processor and memories (3.2V).
VDSP: Voltage to DSP (Digital Signal Processor) (3.2V).
VDSPC: Voltage to DSP (Digital Signal Processor) (2.5V).
VLCD: Negative voltage to the display that controlls the contrast (-2.7V).
VDLCD: Feed voltage to the display.
VRAD: Voltage to the radiopart except the synthesizer.
VRPAD: Voltage to the radiopart in D600 (used to top indicator and buzzer).
VRTC: Voltage to the real time clock.
VVCO: Voltage to the syntesizer.

I2C: Communication standard for two-way communication using only 2
wires, for clock and data.
LO: Local oscillator.
PWM: Puls width modulation.

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2 No serv or can´t place call.

2.1 Find out if the fault is related to
Rx(reciever) or Tx(transmitter).
Connect the phone (with signaling program) to a GSM test instrument and try to get
serv at -68.5 dBm on the input signal. If the phone gets serv proceed to section 2.2.
If the phone doesn´t get serv, there is probably a fault in the LO part or too big
losses in the signal path. Open the phone and check for liquid damages. Make sure
the antenna connection X101 (class A) isn´t mecanically damaged, unsoldered or
dirty (varnish, glue, oxide...) (Fig 2.1).

C532

C535
C531
C534

C530 C533

X101

C850
3 1

C853 N303
4 6
9 8
C851
20 1 N302
N301
C833

C318
Fig 2.1
Look for soldering faults on C318 (class A), N302 and N303 (all three Fig 2.1).
Measure the resistance of C530, C531, C532, C533, C534 and C535 (>200 kOhm,
all are class A, Fig 2.1).
Measure the resistance of C850 (>100 kOhm, class A, Fig 2.1), C851 (>1 kOhm,
class A, Fig 2.1), C833 (>1 kOhm, class A, Fig 2.1) and C853 (>100 kOhm, class
A, Fig 2.1).
Measue VVCO and VRAD (3.8V, Fig 2.2). If any of the voltages are incorrect, pro-
ceed to chapter 3 ("Doesn´t start"-fault).

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32 1
33 128
D105 128 L403
1
L560 N570
D600
64
B510 N401
65
97
96 N560 14 15

VRAD
Z250 Z201
VVCO
Z500
D103
Z202

Fig 2.2
Measure the voltage on pin 4 and 6 on N303 (Fig 2.1). The voltage on pin 4 (the
control voltage) should always vary between 0.8-2.8 V (usually it starts at 1.7 V).
The voltage on pin (the feed voltage) is also variable, but usually it starts at 3.3 V. If
the feed voltage is incorrect (often is it missing completly), check the solderings on
D600:8, D600:102 and also on D105 and D103 (all at Fig 2.2). If the control voltage
is incorrect (mainly 0 or 3.6 V), check the solderings on D600:8 and D600:106-108.
If those are fine, replace N301 (class B, Fig 2.1).
Check the solderings on Z250, Z500, Z201 (GSM 900) and Z202 (GSM1900) (all at
Fig 2.2) plus Z205 (Fig 2.3).
If the fault still remains, send the phone to the next repair level.

Z205
P401

Z204
L223

Z203
Fig 2.3

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2.2 Connect a call.
To test GSM900,connect a call at power level 5 against the instrument with the input
signal at -68.5 dBm. To test GSM1900 use power level 0 and an input signal at -68.5
dBm.
If it works, proceed to section 2.3. If it doesn´t work, then it probably is a TX related
fault. If it is only at channel 1 (or several of the lower channels) you can´t connect a
call, is it N570 (class D, Fig 2.2) that is faulty and the phone can´t be repaired at this
level. Open the phone and check for liquid damages. Make sure the antenna connec-
tion X101 (class A, Fig 2.1) isn´t mecanically damaged, unsoldered or dirty (var-
nish, glue, oxide...).
Measure the resstance between test point P401 (Fig 2.3) and ground (or between
N401:14 (Fig 2.2) and ground). The resistance should be larger than 5 kOhm. If it is

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900) and Z202 (GSM1900)(all at Fig 2.2) plus Z205 (Fig 2.3). If the fault still
remains, send the phone to the next repair level.
If the Rx level value is above 45 steps at input signal -68,5 dBm you need to cali-
brate the phone, therefore send the phone to the next repair level.
If the RX quality value is too high, send the phone to the next repair level.
If the output power is too low, check the solderings on N560 (GSM1900) and N570
(GSM900) (both Fig 2.2). Check the solderings on Z205, Z203 (GSM900) and
Z204 (GSM1900)(all three Fig 2.3). If the fault still remains, send the phone to the
next repair level.

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3 Doesn´t start.

3.1 Find out if the phone will start by using the
On/Off-button.
Attach a fully charged battery and press the On/Off-button. If the phone doesn´t
start, proceed to section 3.2. If the phone starts as normal when it is complete, but
shuts down in the trouble-shooting fixture, measure the current consumption. If it is
>1.5 A or as high as the current limit on the power supply, then N401 (class D, fig
3.1) is faulty and the phone can´t be repaired at this repair level. (Measure the resist-
ance between N401:14 and ground, it should be >10 kOhm, but if N401 is faulty it
usually is about 200 Ohm).

C710
R725 VDIG
N703 N702
B510 R421
C692
32 1 1 28
33 128
D610 1 N401

64 97 14 15
65 96
D600

N701
N412
VDSP N410 VRAD
N411 VVCO
VRPAD
Fig 3.1
If the phone starts, check the charging function by connecting a charger at the sys-
tem connector.If the charging doesn´t work, proceed to chapter 6 ("Charging"-
fault). Open the phone and make a visual check of the board. The side with the com-
ponents are shown in fig 3.1. Check the board for liquid damages and burned or dan-
ages pads at the system connector. Measure the resistance of R421 (0,1 Ohm, class
B, fig 3.1). After every repair of the charging function, you have to verify the
function using the method mentioned in section 6.1.1. Check the solderings on
D600 and D610 (Fig 3.1). As soon as the fault has been corrected, send the phone
back into the normal repair flow. If the phone starts and the values above are correct,
it is either without faults or there is an intermittent fault.

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3.2 Visual check.
Make an outer visual check. Make sure the battery screws are fine and fully
attached, the isolation plate by the battery screw is mounted, the volume buttons are
mounted and the system connector isn´t dirty or liquid damaged. Proceed to section
3.3.

3.3 Current consumption with the On/Off-but-
ton pressed.
Attach a dummy battery and start the phone using the On/Off-button while you
measure the current consumption.
· If the phone doesn´t use any current while pressing the On/Off-button, proceed
to section 3.4.5.
· If the phone uses more than 200 mA, remove the IRDA module and the gold
colored metal plate. Try to start the phone again. If the current consumption got
lower it was either the IRDA-module or the plate that was faulty. If the current
consumption still is too high proceed to section 3.4.3.
· If the phone uses between 1 and 200 mA, starts (asks about a SIM card, search-
ing for a net or something like that) and works as long as the On/Off-button is
being pressed, proceedto section 3.4.4.
· If the phone doesn´t start, try to program it in the flash programmer.
* If the phone doesn´t start in the flash programmer, proceed to section 3.4.1.
* If the phone doesn´t start after programing it or if it is troublesome in the
flash programmer, proceed to section 3.4.2.
* If the phone starts after programming it the fault is probably fixed, but to
eliminate the possibility of intermittent faults, check the board for liquid
damages or bad solderings at D600 and D610 (Fig 3.1).

3.4 Measuring at a powered circuit board.

3.4.1 Doesn´t start in the flash programmer.
Open the phone and check for liquid damages. Make sure the system connector pads
are not burned or damaged. Measure the resistance of R421 (0,1 Ohm, class B, fig
3.1). After every repair of the charging function, you have to verify the function
using the method mentioned in section 6.1.1. Attach the board to the fixture. Keep
the board powered up with high DCIO. Check VDIG and VDSP (3.2 V, Fig 3.1). If
any of the voltages are too low, measure the resistance to ground (VDIG >500 Ohm,
VDSP >25 kOhm). If the resistance is correct, replace the corresponding circuit
(VDIG - N702, class A and VDSP - N701, class A, fig 3.1). If the resistance is too
low, send the phone to the next repair level. If any of the voltages are too high,
replace the corresponding circuit. Check Powerreset (PWRRST) at C710 (>3 V, Fig
3.1). If it is lower, measure the resistance of R725 (100 kOhm, class A, fig 3.1). Is
the resistance correct, replace C710 and N703, (both class A, fig 3.1.) Measure the
voltages on VRAD, VVCO and VRPAD (3.8 V, fig 3.1). If one or more voltages are
incorrect, measure the resistance to ground (>50 kOhm). If the resistance is correct,

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replace the corresponding regulator (fig 3.1, all are class A). If the resistance is too
low, send the phone to the next repair level.

C720

VBATT
4 3
2
5 1 N706

R719

1
V702 3
2
R720 C720:+
V711
Fig. 3.2
Check the amplitude on the "clock" B510:1 (~1v t-t, class C, fig 3.1). Measure the
amplitude using an oscilloscope, spectrum analyzer, frequenzy counter, diode
prob... Ifthe amplitude is too low, send the phone to the next repair level. Check the
solderings on D600 or D610 (fig 3.1). If they are fine and it is sure B510 is okay,
then replace D600 (class B) and D610 (class A). Try to programe it in the flash pro-
grammer between each exchange.

3.4.2 Can be programmed, but doesn´t start afterwards
or is troublesome during programming.
Open the phone and check for liquid damages. Make sure the system connector pads
are not damaged or burned. Measure the resistance of R421 (0,1 Ohm, class B, fig
3.1). After every repair of the charging function, you have to verify the function
using the method mentioned in section 6.1.1. Attach the board to the fixture. Keep
it powered up with DCIO high. Check VDIG and VDSP (3.2 V, fig 3.1). If any of
the voltages are too low, measure the resistance to ground (VDIG >500 Ohm, VDSP
>25 kOhm). If the resistance is correct, replace the corresponding circuit (VDIG -
N702 (class A) and VDSP - N701 (class A)). If the resistance is too low, send the
phone to the next repair level. If any of the voltages are too high, replace the corre-
sponding circuit. Check Powerreset (PWRRST) at C710 (>3 V, Fig 3.1). If it is
lower, measure the resistance of R725 (100 kOhm, class A, fig 3.1). If it is correct,
replace C710 and N703, (both are class A, fig 3.1). Measure the voltages on
VRAD, VVCO and VRPAD (3.8 V, fig 3.1). If one or more of the voltages are
oncorrect, measure the resistance to ground (>50 kOhm). If the resistance is correct,
replace the corresponding regulator (fig 3.1, all are class A) . If the resistance is too
low, send the phone to the next repair level. Check the solderings on D600 or D610
(fig 3.1). If they are fine, replace D610 (class A) and D600 (class B). Try to program
the phone in the flash programmer between each exchange.

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3.4.3 Uses more than 200 mA.
Open te phone and check for liquid damages. Make sure the system connector pads
are not damaged or burned. Attach the board to the fixture. Keep it powered up with
DCIO high. Check the current consumption again, if it uses less than 200 mA, make
sure the gasket in the frame is fine, if it is change the display and the elastomer.
Measure the resistance between VBATT and ground. It should be larger than
1MOhm, if it is lower send the phone to the next repair level. Check VDIG and
VDSP (3.2 V, fig 3.1). If any of the voltages are too low, measure the resistance to
ground (VDIG >500 Ohm, VDSP >25 kOhm). If the resistance is correct, replace
the corresponding circuit (VDIG - N702 (class A) and VDSP - N701 (class A)). If
the resistance is too low, send the phone to the next repair level. If any of the volt-
ages are to high, replace the corresponding circuit. Measure the voltages on VRAD,
VVCO and VRPAD (3.8 V, fig 3.1). If one or more of the voltages are incorrect,
measure the resistance to ground (>50 kOhm). If the resistance is correct, replace
the corresponding regulator (fig 3.1, all are class A). If the resistance is too low,
send the phone to the next repair level.

3.4.4 The phone works as long as the On/Off-button is
pressed.
Open the phone and check for liquid damages. Make sure the system connector pads
are not damaged or burned. Attach the board to the fixture. Keep it powered up with
DCIO high. Measure the voltage on C692 (>3.0 V, fig 3.1). If there is a volt-
age,check the soldering at D600:119(fig 3.1). If there isn´t a voltage, check the
resistance of C692 (>200 kOhm, class A). If the resistance is correct, measure the
input voltage on N706:2 (VBATT, fig 3.2) and the output voltage N706:3 (3.5 V).
Make sure the ground of the regulator exist on N706:1. If VBATT or ground is miss-
ing, the board has to be discarded. If they are correct, replace N706 (class A). If the
output voltage is correct, measure the voltage to ground on the backup capacitors
plus side C720 (3.1 V, class A, fig 3.2). If there are no voltage, measure the resist-
ances over R720 (180 kOhm, class A,fig 3.2) and R719 (47 kOhm, class A,fig
3.2). Are they correct, replace V711 (class A,fig 3.2). If the output voltage is cor-
rect, measure the resistance between the plus side of C720 (fig 3.2) and C692 (fig
3.1), it should be approximately 0 Ohm. If the resistance is too high, is there a foil
damage and the phone has to be discarded. If the fault still remains, send the phone
to the next repair level.

3.4.5 The phone uses no current while the On/Off-but-
ton is being pressed.
Open the phone and check for liquid damages. Make sure the system connector pads
are not damaged or burned. Make sure the keyboard and the keyboard pads are clean
and not damaged, especially the On/Off-button (fig 3.3).

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On/Off-button

ONSRQ

VBATT

Fig. 3.3
Give the board power. Make sure VBATT exists one the marked side of the On/Off-
button (fig 3.3), if it doesn´t, is there a foil damage and the phone has to be dis-
carded. If it exists, measure the resistance from the other side of the On/Off-button,
marked with ONSRQ in fig 3.3, to V702:1 (fig 3.2). It should be approximately 0
Ohm, if it is larger is there a foil damage and the board has to be discarded. Other-
wise replace V702 (class A). If the fault remains, send the phone to the next repair
level.

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4 Audio

4.1 Type of fault.
Make a call to another phone and check the microphone and the earphone. Connect
a handsfree to the phone, make a call and check external microphone and speaker.
· If only the earphone on the phone is silence or if the sound comes and goes, pro-
ceed to section 4.2.
· If the recieving part can´t hear you but you can hear the recieving part, proceed
to section 4.3.
· If you can´t here anything when the handsfree is connected but the recieving part
can hear you, proceed to section 4.4.
· If the recieving part can´t hear you when the handsfree ic connected but you can
hear the recieving part, proceed to section 4.5.
· If neither you or the recieving part can hear anything when the handsfree is con-
nected, proceed to section 4.6.
· If neither you or the recieving part can hear anything, but with the handsfree con-
nected both can hear, proceed to section 4.7.
· If the sound is disturbed, distorted, noisy or something like that, proceed to sec-
tion 4.8.
· If the mute function doesn´t work, proceed to section 4.9.
· If the fault doesn´t fit in to any of the points above, proceed to section 4.10.

4.2 Earphone fault.
Open the phone and check for liquid damages. If there are no, change the front
cover and try again. If the fault remains, replace J810 (Fig 4.1, class A) and try
again.

C816 C815
F601 V805
F600 R635
F602 R605 R602
F606 C841
R727 V703 C840
C842
J810

Fig. 4.1

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Check the solderings on N800:24 and 26 (Fig 4.2). If they are good, measure the
resistance between the connection J810 and ground and also between the two pegs
on the connection. If the resistance to ground is lower than 25 kOhm, then replace
C840 and C841(both class A, Fig 4.1). If the resistance between the two pegs is
lower than 50 kOhm, replace C842 (class A, Fig 4.1). If the fault still remains, send
the phone to next repair level.

R818 R811
C819
C820 R810
C818

C814
16 1
17 64
R814
N800
R812
32 49
33 48

R820

C851 C830
C850 C829
Fig 4.2

4.3 Microphone fault.
Open the phone and check for liquid damages, especially around X830 (Fig 4.3). If
there are no, try to change the front cover and the elastomer and try again.

X830
Fig 4.3

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If the fault remains, check the solderings on N800:13-18(Fig 4.2). If they are good,
measure the resistance of C850 (>100 kOhm, class A, Fig 4.2), C851 (>1 kOhm,
class A, Fig 4.2), C829 and C830 (>100 kOhm, Both are class A, Fig 4.2) and over
C818 and C819 (>100 kOhm, both are class A, Fig 4.2). Measure the resistance of
C815 (Fig 4.1), if the resistance are below 50 kOhm than replace C815 and C816
(both are class A, Fig 4.1). Measure the resistance of R818 (Fig 4.2), the resistance
should be larger than 10 kOhm, if it is lower replace R818 and C820 (both are class
A, Fig 4.2). Measure the resistance of R810 (1 kOhm, class A, Fig 4.2), R811
(1kOhm, class A, Fig 4.2), R812 (1,5 kOhm, class A, Fig 4.2), R814 (470 ohm,
class A, Fig 4.2) and R820 (1,5 kOhm, class A, Fig 4.2). If the resistance of R820 is
too low after R820 has been replaced, replace V805 (class A, Fig 4.1). Measure the
resistance of C814 (>100 kOhm, class A, Fig 4.2). If the fault remains, send the
phone to next repair level.

4.4 Speakerfault together with handsfree.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Check
the solderings on N800:22 (Fig 4.2). Measure the resistance of R804 (Fig 4.4), if the
resistance is lower than 50 kOhm replace F601 (class A, Fig 4.1). If that doesn´t
work then replace R804 (class A, Fig 4.4). Measure the resistance of R806 (100
Ohm, class A, Fig 4.4) and C813 (>100 kOhm, class A, Fig 4.4). If the fault
remains, send the phone to next repair level.

R802
C810 C817 32 1
33 128
R825 C812
R805 D600
C813 64 97
R830 65 96

C835
R804 R806 R636 R601

Fig 4.4

4.5 Microphone fault together with handsfree.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Check
the solderings on N800:19 (Fig 4.2). Measure the resistance of R825 (3.3 kOhm,
class A, Fig 4.4), R830 (470 Ohm, class A, Fig 4.4), R802 (3.9 kOhm, class A, Fig

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4.4) and R805 (15 kOhm, class A, Fig 4.4). Measure the resistance of C835 (>1
kOhm, class A, Fig 4.4) och C817 (>100 kOhm, class A, Fig 4.4), C810 (>10
kOhm, class A, Fig 4.4) and C812 (>100 kOhm, class A, Fig 4.4). If the fault
remains, send the phone to next repair level.

4.6 The handsfree is not detected.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Chekc
the solderings on D600:67 and 70 (Fig 4.4). Measure the resistance of R635 (22
kOhm, class A, Fig 4.1) and R636 (22 kOhm, class A, Fig 4.4). Measure the resist-
ance of R601 (1 kOhm, class A, Fig 4.4) and R605 (1 kOhm, class A, Fig 4.1). If the
fault remains replace D600 (class B, Fig 4.4), if that doesn´t help - send the phone to
next repair level.

4.7 Microphone and earphone fault.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Check
the solderings on D600:67 and 70 (Fig 4.4). Measure the resistance of EXTAUD
(Fig 4.5) to ground, if the resistance is lower than 10 kOhm, replace F600 (class A,
Fig 4.1).

MUTE
PORTHF
EXTAUD
Fig 4.5

Measure the resistance of PORTHF (Fig 4.5) to ground, if the resistance is lower
than 10kOhm, replace F602 (class A, Fig 4.1). Measure the resistance of R635 (22
kOhm, class A, Fig 4.1) and R636 (22 kOhm, class A, Fig 4.4). Measure the resist-
ance of R601 (1 kOhm, class A, Fig 4.4) and R605 (1 kOhm, class A, Fig 4.1). If the
fault still remains, replace D600 (class B, Fig 4.4). If that doesn´t help, send the
phone to next repair level

4.8 Signal treatment fault.
Open the phone and check for liquid damages. Power up the board. Check VDIG
and VDSP (both should be 3.2V, Fig 4.6). If one of the values are incorrect then pro-
ceed to chapter 3 ("Doesn´t start"-fault). Check VDSPC (should be 2,5V, Fig 4.2). If

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VDSPC is too low, then measure the resistance to ground. If the value is lower than
10 kOhm, then replace, one by one and check the resistance between, C903 (Fig
4.6), C904 (Fig 4.6), C905 (Fig 4.6), R727 (Fig 4.1) and D900 (Fig 4.6), all of them
are class A. If VDSPC is too low and the resistance to ground are larger than 10
kOhm, then replace V703 (class A, Fig 4.1). If the feed voltages are correct, then
check the solderings on D600 (Fig 4.4), D900 (Fig 4.6) and N800(Fig 4.2). If the
solderings are correct, then first replace D900 (class A, Fig 4.6) and try again. If that
didn´t help, then replace D600 (class B, Fig 4.4). If the fault still remains, send the
phone to next repair level.

C904

C903 VDSPC
D900
R703 VDIG
C905

VDSP
Fig 4.6

4.9 Music mute fault.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Check
the solderings on D600:69 (Fig 4.4). Measure the resistance of R602 (470 ohm,
class A, Fig 4.1). Measure the resistance MUTE (Fig 4.5) to ground. If the resist-
ance is lower than 100 kOhm, then replace F606 (class A, Fig 4.1). If the resistance
is correct, then replace D600 (class B, Fig 4.4). If the fault remains, send the phone
to next repair level.

4.10 Audio fault.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Power
up the borad. Check VDIG and VDSP (both should be 3.2V, Fig 4.6). If any of the
voltages incorrect, proceed to chapter 3 ("Doesn´t start"-fault). Check VDSPC
(Should be 2.5V, Fig 4.6). If VDSPC is too low then measure the resistance to
ground. If the value is lower than 10 kOhm, then replace, one by one and check the
resistance between, C903 (Fig 4.6), C904 (Fig 4.6), C905 (Fig 4.6), R727 (Fig 4.1)
and D900 (Fig 4.6), all of them are class A. If VDSPC is too low and the resistance
to ground is larger than 10 kOhm, then replace V703 (class A, Fig 4.1). If the feed

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voltages are correct then check the solderings on D600 (Fig 4.4), D900 (Fig 4.6) and
N800 (Fig 4.2). Measure the resistance of R703 (0 ohm, class A, Fig 4.6) and C850
(>100 kOhm, class A, Fig 4.2), C851 (>1 kOhm, class A, Fig 4.2). If the fault
remains, send the phone to next repair leve.

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5 Display fault

5.1 Type of fault.
Start the phone with a fully charged battery using the On/Off-button.
· If the phone doesn´t start, proceed to chapter 3 ("Doesn´t start"-fault).
· If the display missis one or more segments, proceed to section 5.2.
· If the display shows nothing at all, proceed to section 5.3.

5.2 One or more segments are missing.
Open the phone and check for liquid damages. If there are no, change the display
and try again.

5.3 The display shows nothing at all.
Start the phone with a dummy battery and check the current consumption (should be
lower than 200 mA). Open the phone and check for liquid damages or if the display
is mecanically damaged. If there are no damages, replace the elastomer and try
again. If that didn´t make it , change the display and try again. If the current con-
sumption is larger than 200 mA, then proceed to chapter 3 ("Doesn´t start"-fault).
Give the board power and start it up without the display. Measure the voltages on
the display pads H623, Fig 5.1.

7. Not connected
6. I2CDAT 3.2V
5. VLCD -2.7V
4. VDLCD 3.2V H623 7

3. GND 0V
1

2. I2CCLK 3.2V
1. RESETO 3.2V

Fig 5.1

If one or more of the voltages are incorrect, proceed to the corresponding section
below. To see the components placing go to Fig 5.2.
RESETO: If the value is incorrect, measure the resistance between the pad and
D600:77, check also the soldering at the same pin. It should be 0 ohm, if it is con-
siderable larger is there a foil damage and the phone has to be discarded. If the
resistance is correct, replace D600 (class B).
I2CCLK: If the value is incorrect, measure the resistance between the pad and
D600:4. It should be 10 kOhm, if it is larger measure the resistance of R615 (10
kOmh). If R615 is faulty, replace it (class A). If R615 is correct is there a foil dam-

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age and the phone has to be discarded. Check VDIG on R620 (2,2 kOhm, class A),
if it is lower than 3,2 volt proceed to chapter 3 ("Doesn´t start"-fault). If the things
above are correct replace D600 (class B).
Is ground and should be 0 volt.(Measure the resistance to another ground point.)
VDLCD: If the value is incorrect, measure the resistance between the pad and
D600:45, it should be 0 Ohm. If it is correct, measure the resistance between the pad
and ground it should be larger than 2,5 MOhm. If it isn´t, replace C615 and C674
(both are class A). If that didn´t make it, replace D 600 (class B).
VLCD: If the value is incorrect, measure VDIG at N702:5, it should be 3,2 volt.
Measure the resistance between the pad and V611:1, it should be 0 Ohm, otherwise
is there a foil damage and the phone has to be discarded. Check the solderings on
D600:95 and D600:96. Measure the voltages on V611 pin 1=-2,7 V, pin 2=-1,6 V
and pin 3=-2,5 V. Do the same on V608 pin 1=-1,6 V, pin 2=0 V and pin 3=-1,0 V.
If any of the voltages are incorrect, replace the diode (or both) and try again. If the
fault still remains, measure the resistance of C632, C634 and C636, they should be
larger than 2,5 MOhm. Measure the resistance of C631 and C633, they should be
larger than 100 kOhm. Measure the resistance of C824, it should be larger than 25
kOhm. If any of the capacitors are faulty, replace it (they are all class A).Measure
also the resistance of R616 and R639 (100 kOhm), R807 (82 kOhm) and R808 (33
kOhm). If anyone is incorrect, replace it (they are all class A).If the fault still
remains, replace D600 (class B).
I2CDAT: If the value is incorrect, measure the resistance between the pad and
D600:3, it should be 10 kOhm. Is it larger, then measure the resistance of R614 (10
kOhm). If R614 is faulty, replace it (class A), is R614 correct then there is a foil
damage and the phone has to be discarded. Measure VDIG on R619 (2,2 kOhm,
class A), if it is lower than 3,2 volt, proceed to chapter 3 ("Doesn´t start"-fault). If
the things above are correct, replace D600 (class B).
If the fault still remains, send the phone to the next repair level.

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R619 N702:5
32
33
1
128 R620

97
64
65 96 D600

R808
C824 R807
C633 3
V608
1 2
C632 R639
C636
C634 21
R616 V611 3

R615
C631

C615

R614
Fig 5.2 C674

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6 Charging fault

6.1 Type of charging fault.
Do a visual check of the battery screws and the system connector. Change if neces-
sary. Start the phone with the On/Off-button and a fully charged battery.
· If it doesn´t start, proceed to chapter 3 ("doesn´t start"-fault).
· If the phone starts and shows charging at once, proceed to section 6.2.
· If the phone doesn´t show charging, turn it of and connect a charger to the sys-
tem connector. If it indicates charging in the display and the red top indicator
shines, the phone is okay. If it doesn´t show anything in the display and the red
top indicator doesn´t shine, proceed to section 6.3.
· If the battery doesn´t charge, even if the phone shows it does, proceed to section
6.4.
· If the phone starts and shows charging, but the red top indicator doesn´t shine,
proceed to chapter 9 ("Illuminatin and buzzer"-fault).

6.1.1 Verification of the charging function.
Attach a real battery to the phone. The batterys voltage must be high enough to get
the phone started, otherwise will not the charging begin at once. Cut a piece of cable
from a charger and make a charging test cable. Connect the charging test cable to a
power supply that shows the current consumption. Make sure the positive side from
the power supply connects to DCIO (the lonely pin on the system connector, pin
12). You can also use a normal charger with an ammeter connected in serie. Set the
power supply on 7.6 V and current limitation on 700 mA. Connect the charging
cable to the phones system connector and check the current consumption.
If the phone starts and shows charging in the display and the current consumption
on the power supply varies between ~700 mA (the solution with a normal charger
and a ammeter gives ~500-800 mA depending on what kind of charger you use) and
~5 mA with a few seconds interval, is there no charging fault.
After every repair of the charging function, you have to verify the function using the
method mentioned above.

6.2 Shows charging without a charger con-
nected.
Open the phone and check for liquid damages. Give the board power and start it
with the On/Off-button.

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GND
DCIO

V704 VBATT 1 20

10 11

N450
Fig 6.1

Check the feed voltages VDIG (3.2 V) on the side that is marked of C600 (Fig 6.2)
and VRAD (3.8 V) on N450:13 (Fig 6.1) and measure the resistance of R703 (class
A, 0 Ohm, Fig 6.2). If any of the feed voltages ar incorrect, proceed to chapter 3
("Doesn´t start"-fault). If the feed voltages are correct, send the phone to the next
repair level.

R703
V401
C600
R411
R421
Fig 6.2

6.3 Doesn´t begin to charge.
Open the phone and check for liquid damages. Make sure the system connector pads
are not burned or oxidized, especially on GND pin 10 (Fig 6.1). Measure the resist-
ance between DCIO and VBATT (390 Ohm, Fig 6.1). If the resistance is too low,
replace V401 (class A, Fig 6.2). If it is too high, measure the resistance of R421 (0.1
Ohm, class B, Fig 6.2). Measure the resistance of R411 (390 Ohm, class A, Fig 6.2).
If R421 and R411 are correct and the resistance between DCIO and VBATT is still
too high, is there a foil damage and the board has to be discarded. Give the board
power and start it by grounding N450:6 (Fig 6.1). If it doesn´t start, replace V401
(class A). If that didn´t make it, replace V704 (class A, Fig 6.1).

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After every repair of the charging function, you have to verify the function using the
method mentioned in section 6.1.1.
If the fault still remains, send the phone to the next repair level.

6.4 The phone starts, but doesn´t charge, even
though it shows charging.
Open the phone and check for liquid damages. Make sure the system connector pads
are not burned or oxidized, especially on GND pin 10 (Fig 6.1). Measure the resist-
ance between DCIO and VBATT (390 Ohm, Fig 6.1). If it is too high, measure the
resistance of R421 (0.1 Ohm, class B, Fig 6.2). Measure the resistance of R411 (390
Ohm, class A, Fig 6.2). If R421 and R411 are correct and the resistance between
DCIO and VBATT is still too high, is there a foil damage and the phone has to be
discarded.
After every repair of the charging function, you have to verify the function using the
method mentioned in section 6.1.1.
If the fault still remains, send the phone to the next repair level.

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7 SIM fault (Insert card)

7.1 What is a SIM fault?
Attach a fully charged battery and a SIM card to the phone.
· If the phone shows "Wrong card" or "Insert correct card" when started, then
the phone is SIM locked and can´t be repaired at this repair level.
· If the phone shows "Phone lock", then it is locked by the customer with a per-
sonal code. The phone will be unlocked in the reset program in the normal repair
flow.
· If the phone shows "PIN?" or "Enter Pin", then the SIM card is locked with a
pesonal code.
· ONLY IF IT SHOWS "INSERT CARD" IS IT A SIM FAULT.

Open the phone and check for liquid damages. If there are no, put the phone back
together using a new SIM holder and try again. If it still doesn´t work open the
phone again. Check the solderings on D600:72-75 (Fig 7.2).

GND
SIMVCC
SIMCONRST
SIMCONDAT
SIMCONCLK

Fig. 7.1

Measure the resistance between the SIM pads in fig 7.1 and ground. Check the
ground on GND by measuring the resistance between GND and another ground
point. It should be approximately 0 Ohm, if it is larger the board is faulty and has to
be discarded. Between SIMVCC-, SIMCONRST-, SIMCONDATA- and SIMCON-
CLK-pads and ground should the resistance be larger than 40 kOhm. If it isn´t,
replace as follow: for SIMMVCC: C625, C626, C627 and R618, for SIMCONRST:
C628, for SIMCONDAT: C630 and for SIMCONCLK: C629, all are class A,fig
7.2.

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R680 R684 D600

R686

32 1
33 128

7 1
D602 8 14 64 97
65 96
C626
R618
C625
C627
C630
C628
R600
C629
R627 C638 R617 R628
Fig. 7.2

Measure the resistance of R600 - 33 Ohm, R617 - 15 kOhm, R627 - 33 Ohm, R628
- 33 Ohm, R680 - 15 kOhm and R684 - 33 Ohm. If any resistor are incorrect,
replace it, all are class A, fig 7.2.
Give the board power and start it up. Measure the voltage on D602:1 (3.2 V, class A,
fig 7.2). If the voltage is lower, measure the resistance of R686 (4,7 kOhm, class A,
fig 7.2). If the resistance ic correct, then VDIG is incorrect and you have to proceed
to section 3: "Doesn´t start"-fault. Measure the voltages on D602:12 - 0 V and
D602:13 - 3,2 V. If any of the voltages are incorrect, replace C638 (class A, fig 7.2).
If that didn´t make it, replace D602 (class A, fig 7.2).
If all values are correct, replace D600 (class B, fig 7.2). If that didn´t make it,
replace D602 (class A, fig 7.2).
If the fault still remains, send the phone to the next repair level.

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8 Keyboard

8.1 Type of keyboard fault.
Put in a Sim card and a fully charged battery. Start the phone with the On/Off but-
ton. If it doesn´t start, proceed to chapter 3 ("Doesn´t start"-fault). Press all buttons
(remember the volume buttons) and verify which doesn´t work. This is an easy way
to do the verification: go to Menu/Settings/Key sound and choose Click. press the
buttons 1,2,3.. ...*,0,#. You should hear a click sound and the corresponding figure
shown in the display when you press each button. Then press Yes, No, Clr, "<" and
">". When pressing "Yes" the phone tries to make a call, press "No" and the phone
should disconnect the call, press "<" or ">" and you scroll the menues and "clr"
clears the display from the figures that came up. Press the two volume buttons, you
should hear a click sound each time. If one or both volume buttons are faulty, pro-
ceed to section 8.2. Close the flip over the keyboard, you should hear a click sound
just before it is fully closed. If there is no click sound when you close the flip, pro-
ceed to section 8.3. If one or more of the buttons are faulty, proceed to section 8.4.

8.2 The volume buttons are faulty.
Open the phone and check for liquid damages, especially around X820 (Fig 8.1).
Change the flex film for the volume buttons, put the phone together and try again.

C658 C687
C688 X820
C659 32 1
C657 C689

Fig 8.1

Measure the resistance between the pads on X820 to ground. All three should have a
resistance larger than 1 MOhm. If the resistance is lower, proceed to point 1 other-
wise proceed to point 2.
1. If the resistances are too low replace as follow; X820:1 replace C659 and C689;
X820:2 replace C658 and C688; X820:3 replace C657 and C687. (all capacitors are
class A, Fig 8.1). If the fault remains, replace D600 (class B, Fig 8.2).
2. Check the solderings on D600:122-123 (Fig 8.2) and D600:128. Measure the
resistance on the foil between X820:1-D600:122, X820:2-D600:128 and X820:3-
D600:123. If there is a damage in the foil the board has to be discarded.If no fault is
found replace D600 (class B).

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8.3 Flip fault.
Make sure that the little plastic "spike" that pushes the little button just below 0 and
# isn´t broken. If it is broken, change the flip and try again. If the fault remains, open
the fault and check for liquid damages, especially around the little button men-
tioned above (Fig 8.4). Wash the keyboard pad properly and put the phone together
again using a new keybord. If the fault still remains, proceed to section 8.4 (the but-
ton to the flip is called Flip in Fig 8.3).

D600 VDIG C600

32 1
33 128

64 97
65 96

Fig 8.2

8.4 Keyboard fault.
Open the phone and check for liquid damages, especially around the buttons that
don´t work. Wash the keyboard pads properly and put the phone together again
using a new keyboard. Check the phone again according to section 8.2. If that didn´t
work, open the phone and check the solderings on D600:1 (Fig 8.2) and D600:120-
128. If they are fine, give the board power and start it up. Measure VDIG (3.2 V) on
the side of C600 that is marked (Fig 8.2). If VDIG is incorrect, proceed to chapter 3
("Doesn´t start"-fault).
Function chart is shown in Fig 8.3.

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Row 1 D600:125 1 2 3

Row 2 D600:124 5 6 Flip
4
X820
Row 3 D600:123 3
7 8 9
2
Row 4 D600:122 * 0 # 1

Row 5 D600:120 >
< Yes Clr
VBATT
column 1 D600:126

column 2 D600:127
NO
column 3 D600:1

column 4 D600:128 ONSRQ

Fig 8.3

Make sure there is a voltage (3.2 V) on the faulty keyboard pads according to Fig
8.4 below. Note! The No button has 4.8 V and the flip button looks different.

No button
To column

Measure the voltage on the
"E"-shaped pad.

Flip-button (measure the voltage on the left part).
Fig 8.4

If the voltage is missing on a complete row, measure the voltage on the correspond-
ing pin at D600 (Fig 8.3). If the voltage is correct on the pin there is a foil damage
and the board has to be discarded. If the voltage is missing on the pin to, replace
D600 (class B).

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If the voltage is missing on a part of a row, e.g on button 2 and 3 but not on button 1,
is there a foil damage and the board has to be discarded. Verify by measuring the
resistance between a working pad and a faulty pad.
If a complete column is missing, measure the resistance between the pad (Fig 8.4)
and the corresponding pin at D600 (Fig 8.3)(measure on the "c"-shaped side of the
pad). If there is a foil damage the board has to be discarded. If the foil is okay,
replace D600 (class B). If a part of a column is faulty, measure the resistance
between the pads in the column to verify a foil damage.

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9 Illumination and buzzer.

9.1 Type of fault.
Attach a dummy battery and a sim-card to the phone, press the On/Off-button and
wait until the phone has got serv. (Against an instrument or a real network).
· If the phone doesn´t make a beep when started, go to Meny/Ring level and raise
the volume to max. Try again, if it still doesn´t make a beep or if it makes a low
beep, proceed to section 9.2.
· If the illumination and/or the display light isn´t lit up when started, proceed to
section 9.3.
· If the top indicator doesn´t flash with green light when the phone has got serv,
proceed to section 9.4.
· When the phone has got serv and flashes with green light, lower the battery volt-
age to 4.2V. The top indicator should start to flash with red light after a while, the
battery indicator show an empty battery and warn with a beep.
* If the battery indicator doesn´t show an empty battery and the phone
doesn´t make a beep or flash with red light you will have to perform a battery
calibration.
* If the phone does show an empty battery and makes a beep but doesn´t flash
with red light, proceed to sedtion 9.5.

9.2 The buzzer is faint or dead.
Open the phone and check for liquid damages. If the buzzer is faint, then check the
buzzer gasket in the front cover. If it is squeezed, partly or completly covers the hole
in the front cover, then change the front cover and try again. If that didn´t help, then
check the buzzer, H600 (class A, Fig 9.1) for bad solderings. If the solderings are
fine, replace the buzzer. Put the phone together and check the buzzer again accord-
ing to section 9.1. If the fault is gone, send the phone trough the regular flow.
If the fault remains, dismount the phone and give the board power. Measure the volt-
age on H600:3 (4.8V). If the voltage is missing or incorrect, check the voltage on
both sides of R606 (Fig 9.1). Ii it is missing on one side measure the resistance of
R606 (10 Ohm, class A, Fig 9.1), if the resistance is correct, then replace C619 and
C620 (class A, Fig 9.1). If the voltage is incorrect on both sides, measure VBATT
(4.8V, Fig 9.1). If VBATT is incorrect, proceed to chapter 3 ("Doesn´t start"-fault).
If VBATT is correct, measure the resistance to R606 (the side nearest the edge of
the board), if there is an interruption (larger than approximately 0 Ohm), the phone
has to be discarded. Check the soldering at D600:91 (Fig 9.2), if it is fine then meas-
ure the resistance between the same pin and V606:1 (Fig 9.1), the resistance should
be 1.0 kOhm.

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R606
V606
V606:1 C620
H600:3

VBATT H600
Fig. 9.1 C619

If the resistance is incorrect, then replace R651 (class A, Fig 9.2). Didn´t that make
it there is a foil damage and the phone has to be discarded. Measure the resistance
from V606:1 to ground, if the resistance is lower than 2 MOhm then replace C653
(class A, Fig 9.2). If the resistance is correct, then replace V606 (class A). If that
didn´t make it replace D600 (class B).
If the fault still remains, send the phone to the next repair level.

32 1 D600
33 128
R651
64 97
65 96
C653

Fig. 9.2

9.3 Illumination fault.
Open the phone and check for liquid damages. Make sure all 10 LEDs H651-H660
(class A, Fig 9.1), are mounted and correct soldered.

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Give the phone power and start it up. If only a few, but not all, LEDs in a group,
H651-H654 (display light) or H655-H660 (keyboard illumination), are not lit
replace them. If H655 and H656 are not lit, measure the resistance of R659 (33
Ohm, class A, Fig 9.3). If a complete group, H651-H654 or H655-H660, are not lit
but the other group are, measure the resistance of one of the LEDs in the group. If
the resistance is lower than 1 MOhm, one of the LEDs are faulty. replace them one
by one until the fault is gone. If the resistance of the LEDs are correct, measure the

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9.4 Green top indicator doesn´t work.
Open the phone and check for liquid damages. Make sure the double LED H650
(class A, Fig 9.4) is correctly soldered.

C654 C655
H650:3
R646
H650:1

C621

H650
H650:2

Fig. 9.4
If the soldering is fine, give the phone power and start it up. Measure the voltage on
H650:2 (Fig 9.4), itshould be 3.8 V. If it is correct, replace H650 (class A). If it is
missing, measure the resistance of R646 (470 Ohm, class A, Fig 9.4). If that resist-
ance is correct, measure the resistance of C621, it should be larger than 10 kOhm, if
it isn´t then replace C621, C614 and C432 (all are class A, Fig 9.4 and 9.5) one by
one and check the resistance after every replace. If the resistances are correct, meas-
ure the voltage on N411:5 (Fig 9.5), it should be 3.8V. If the voltage is incorrect
then replace N411 (class A). If the voltage is correct but not on H650 and the resist-
ance of R646 (Fig 9.4) is correct there is a foil damage and the phone has to be dis-
carded.

C614

C432
N411
N411:5
Fig. 9.5
Measure the resistance of C654 (class A, Fig 9.4), it should be larger than 1 MOhm,
if not replace the capacitor. Check the soldering at D600:94 (Fig 9.2). If the solder-
ing is fine, measure the resistance between D600:94 and H650:3. If there is a foil

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