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Trouble Shooting Guide, Standard
Trouble Shooting Guide, Standard
Applicable for R320s and R320sc
Contents
1 Explanations ....................................................................................................................2
2 Network Problems...........................................................................................................5
3 On/Off Problems .............................................................................................................9
4 Audio Problems .............................................................................................................12
5 Display/Illumination Problems ....................................................................................15
6 Capacity/Charging Problems.......................................................................................17
7 SIM Problems................................................................................................................18
8 Key Problems.................................................................................................................19
9 Alert Problems...............................................................................................................20
10 Data Communication Problems...................................................................................23
11 Other Problems .............................................................................................................24
12 Software Problems ........................................................................................................25
13 Revision History ............................................................................................................26
4/00021-2/FEA 209 544/21 B Approved according to 1776-2/FEA 209 544
Trouble Shooting Guide, Standard
1 Explanations
For component placing see document 1078-2/FEA 209 544/21
1.1 Pin Placing
Single diode (PIN diode). Electrolytic capacitor.
Double diode or single Five pin circuit (usually Double transistor.
transistor. voltage regulator).
Eight pin circuit. Ten pin circuit. Sixteen pin circuit
Crystal N200 N234
4/00021-2/FEA 209 544/21 B 2(26)
Trouble Shooting Guide, Standard
1.2 Abbreviations
B: Crystal.
C: Capacitor.
D: Digital circuit.
F: Overvoltage protection.
H: Buzzer, LED, pads for display.
J: Connector.
L: Coil.
N: Analogue circuit.
R: Resistor.
S: Keyboard pads.
U: BALUN Component that converts a balanced signal to an unbalanced or the other way
around.
V: Transistor, diode.
X: Contact surface on the circuit board.
Z: Filter.
DCIO: DC voltage through the system connector for charging.
GND: Ground.
EL_HIGH: Logical signal that activates the background illumination.
EL_LOW: Logical signal that activates the background illumination.
ONSWAn: Voltage from the On/Off key that starts the phone.
RTC: Real Time Clock. The clock that keeps track of time.
SIMCLK: Signal from the processor used for communication to SIM, clock signal.
SIMDAT: Signal from the processor used for communication to SIM, data signal.
SIMRST: Signal from the processor used for communication to SIM, reset signal.
SIMVCC: Feed voltage for SIM.
VBATT: Battery voltage.
VCORE: DC voltage for the processor and memory at, for instance, stand by mode.
Lower than VDIG.
VDIG: DC voltage for the processor and memory.
VDSPC: DC voltage for the DSP (Digital Signal Processor).
VLCD: DC voltage for the display that controls the contrast.
VRAD: DC voltage for the radio part except the synthesizer.
V380B: DC voltage for the radio part.
VRTC: DC voltage for the real time clock.
VVCO: DC voltage for the synthesizer.
4/00021-2/FEA 209 544/21 B 3(26)
Trouble Shooting Guide, Standard
I2C: Communications standard for two-way communication using only 2 wires,
clock and data.
4/00021-2/FEA 209 544/21 B 4(26)
Trouble Shooting Guide, Standard
2 Network Problems
2.1 Find out if the problem is Rx- or Tx-related
Connect the phone (with signalling program) to a GSM test instrument and try to get SERV at
an input signal strength of -68.5dBm.
If the phone does not get SERV, go to section 2.2.
If the phone gets SERV, go to section 2.3.
2.2 The phone does not get SERV
Open the phone and check for liquid damage.
Make sure that the antenna connector (W100, Fig. 2.1) is correctly soldered, and not
mechanically damaged, dirty or oxidised. Clean, resolder or replace if needed.
Fig. 2.1
Check the soldering of N234, N200, Z200 and Z201.
Measure the resistance of R220, R221, R222 and R223, (all 0 ohm).
Replace if incorrect.
Check C312 for bad soldering, resolder carefully if necessary.
Retry to get SERV again with the settings mentioned above.
If the phone gets SERV, go to section 2.3.
If the phone still does not get SERV it is probably within the LO part that the fault lies or the
losses in the signal path are too large. It is also possible that the feed voltages are incorrect.
Open the phone.
Power up the board and start it by pressing the On/Off key.
4/00021-2/FEA 209 544/21 B 5(26)
Trouble Shooting Guide, Standard
Measure the VRAD voltage at C501, at the side close to N700 (3.80 V).
If the voltage is incorrect, send the unit on according to the local company directives
Measure the V380B voltage at C500, at the side close to C421 (3.80 V).
If the voltage is incorrect, send the unit on according to the local company directives
Measure the VVCO voltage at pin 5 of N502 (3.80 V).
If the VVCO voltage is correct, go to section 2.2.1.
If the voltage is incorrect, measure the voltage at L500 (3.70 V), at the side close to C503.
If the voltage at L500 is correct, measure the voltage at V500, at the side close to N700. It
shall be more than 4.10 V.
If the voltage at V500 is correct, measure the voltage at pin 1 of N502, it shall be more than
4.10 V.
If the voltage at pin 1 of N502 is incorrect send the unit on according to the local company
directives.
If the voltage at pin 1 of N502 is correct, measure the voltage at pin 3 of N502 (3.80 V).
If the voltage at pin 3 of N502 is correct, replace N502.
If the voltage at pin 3 of N502 is incorrect send the unit on according to the local company
directives
If the voltage at V500 (at the side close to L500) is 3.70 V, replace V500, otherwise send the
unit on according to the local company directives.
If the voltage at L500, at the side close to C503, is incorrect, measure the resistance of L500
(0 ohm).
If the resistance is correct, send the unit on according to the local company directives
If the resistance is too high, replace L500.
2.2.1 Check the feed voltages
The VRAD voltage for N234:
Measure the voltage at pin 5 of N234 (3.80 V).
If the voltage is incorrect, measure the resistance of L211 (0 ohm).
If the resistance is incorrect, replace L211.
If the resistance is correct, measure the resistance from one the sides of L211 to ground (2
Mohms).
If the resistance from L211 to ground is incorrect, replace C214, C211 and C212.
Measure the voltage at pin 47 of N234 (3.80 V).
If the voltage is incorrect, measure the resistance of R345 (18 ohms).
If the resistance is incorrect, replace R345.
If the resistance is correct, measure the resistance from pin 47 of N234 to ground (2Mohms).
If the resistance from pin 47 of N234 to ground is incorrect, replace C345 and R345.
4/00021-2/FEA 209 544/21 B 6(26)
Trouble Shooting Guide, Standard
Measure the voltage at pin 62 of N234 (3.80 V).
If the voltage is incorrect, measure the resistance of L370 (0 ohm).
If the resistance is incorrect, replace L370.
If the resistance is correct, measure the resistance from one of the sides of L370 to ground (>1
Mohm).
If the resistance from L370 to ground is incorrect, replace C373 and R362.
The VVCO voltage for D300:
Measure the voltage at R303 (3.80 V), at the side close to R346.
If the voltage is incorrect, measure the resistance of R303 (18 ohms).
If the resistance is incorrect, replace R303.
If the resistance is correct, measure the resistance at R303, (at the side close to R346), to
ground (130 kohms).
If the resistance at R303 is incorrect, replace C303.
Measure the voltage at the marked side of R334 (3.80 V).
If the voltage is incorrect, measure the resistance of R334 (10 ohms).
If the resistance is incorrect, replace R334.
If the fault remains, send the unit on according to the local company directives.
2.3 Connect a call at