Trouble Shooting Guide, Standard
4/00021-2/FEA 209 544/21 B 15(26)
5 Display/Illumination Problems
5.1 Type of problem
Insert a fully charged battery into the phone and start it up by pressing the On/Off key.
If the phone does not start, go to chapter 3 (“On/Off ”-problems).
If the display is missing one or more segments, go to section 5.2.
If nothing shows on the display, go to section 5.3.
5.2 Segments are missing.
Change the display unit and adjust the contrast according to STANDARD REPAIR PACKAGE
TEST DESCRIPTION R320 and try again.
5.3 Nothing shows on the display
Open the phone and check for liquid damage.
Power up the board and start it up without the display mounted.
Measure the voltages at the display pads (H623).
Pad 1: RES.B 2.75 V
Pad 2: VDD 2.75 V
Pad 3: SDA 2.75 V
Pad 4: SCL 2.75 V
Pad 5: VSS 0 V
Pad 6: VLCD 0 V
If SDA or SCL voltage is missing, check the VDIG voltage (2.70 V).
If the VDIG voltage is correct, measure the resistances of R619 (6.8 kohms), R620 (6.8
kohms), R615 (0 ohm) and R614 (0 ohms). Also measure the resistance over C675 and C676
>1Mohm.
If any of the resistances are incorrect, replace the corresponding component.
If the fault remains, change the display unit and adjust the contrast according to STANDARD
REPAIR PACKAGE TEST DESCRIPTION R320 and try again.
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