Nokia 3155i Troubleshooting Manual

Also see for 3152: User guide Rf description and troubleshooting Disassembly instructions User guide Reassembly

Nokia 3155i Troubleshooting Manual Manual pdf 20 page image

3155/3155i (RM-41), 3152 (RM-61)Baseband Description and TroubleshootingPage 20 ©2005 Nokia Corporation Company Confidential ISSUE 1 07/2005DisplayHow the Display WorksNokia 3155/3155i/3152 has a large main display (160 x 130 color depth), controlled bythe D2800 engine through a parallel interface. The secondary, black and white display(96 x 68) is controlled by the D2800 engine through a serial interface. The UEMEKpowers using VIO and VFlash1.Figure 18: Nokia 3155/3155i/3152 UI DisplayDisplay TroubleshootingWhen troubleshooting the display, make these common checks (see Figure 19):• Check that the display is connected properly and is making good contact withLCD connector. If no display, replace the LCD.• Check the power supply VIO and VFlash1. If not correct, check the UEMEK.• Check the activity on the LCD test points. If no activity, check or replace D2800• Check the parallel interface (DIF) for the main display• Check that the DIF CLk is 4.8MHz• Check the serial interface (LCD) for the secondary display• Check that the LCD CLk is 2.4MHzMain display:262K color (128x160)Secondary display:Black & White (96 x 65)4-way navigationkey with center-selectExternal keysSoft keysUHJ Headset jack/sliding coverVolume keyPush-to-Talk key