C905
1222-9526 rev. 1
TROUBLESHOOTING
Display Illumination Problems
TROU
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OTIN
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- Opto Sensor Problems
START
Step 1:
Flash the Phone with EMMA SUCR SW
If successful claim SW Flash
If not go to step 2.
Step 2:
Load ITP SW into the Phone
Use TRS Fixture
Connect:
PBA Key Flex Flip, Slider FPC Assy and Display
to the PBA
Connect: VBATT and DCIO/SEPI
Use Fault Trace SW and go to:
MMI
Misc
Init Screen Testing
Led and Backlight
Activate:
Display Backlight
If Display Backlight is working on the TRS Fixture
then Replace
Display, PBA Key Flex Flip or Slider FPC Assy
If not then continue with the
Display ilumination Problems TRS guide
1:
Ues Fault trace SW and go to:
MMI
Misc
Init Screen Testing
Led and Backlight
Deactivate:
Display Backlight
2:
Disconnect Slider FPC Assy from the PBA
3.7V - 3.8V DC
at MP 51 (TP4200)
3.7V - 3.8V DC
at MP 119
(V4201_Anode)
No
Replace
V4201
Yes
Replace
L4200
No
Fault trace SW
MMI
Misc
Init Screen Testing
Led and Backlight
Activate:
Display Backlight
Yes
17V - 20V DC at
MP 51 (TP4200)
More than
4 Volt DC
Pk-Pk Pulses
at MP 117
(V4200_Pin 3)
No
Yes
Replace
V4200
SL 5 Replace
N2000
SL 4 Escalate
No
0 Volt DC at
MP 52 (TP4201)
Yes
Replace
X4200
Yes
Replace
V4203
No
Is the
Display illumination
Problem solved
No
Claim Component
V4203
Yes
Display Illumination Problems
START
Step 1:
Replace PBA Key Flex Flip
and retest the Phone
If successful claim PBA Key Flex Flip
if not go to step 2.
Step 2:
Replace Slider FPC Assy
and retest the Phone
If successful claim Slider FPC Assy
if not continue with the
Opto Sensor Problems TRS guide
Is the
Display
Illumination (LEDs)
Ok
Go to
Dispaly illumination
Problems TRS guide
No
Can you see
any picture on
Display
Yes
Go to
Display Problems
TRS guide
No
Use TRS Fixture
Connect: VBATT and DCIO/SEPI
Yes
1.8 Volt DC at
MP 73 (R2217
OPTO_EN)
Shortly after phone
Power On
SL 5 Replace
N2000
SL 4 Escalate
No
Yes
3 Volt
Pk-Pk Pulses at
MP 59 (TP2203
VOPTO30) Shortly after
phone Power On
No
Replace
N2201
Replace
X4200
Yes
Is the
Opto Sensor Problem
solved
Claim Component
X4200
No
Yes
SL 5 Replace
N2000
SL 4 Escalate
Opto Sensor Problems
SEMC Troubleshooting Manual
11
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