Introduction To Nem-4 Troubleshooting; General Guidelines For Nem-4 Trouble Shooting; Tools Needed For Troubleshooting; General Guidelines - Nokia NEM-4 Series Troubleshooting Instructions

CCS Technical Documentation

Introduction to NEM-4 Troubleshooting

This document is intend to be a guide for localizing and repairing electrical faults in the
NEM-4 device. First there is a brief guide for fault localizing. Then fault repairing is
divided into Troubleshooting paths.
Before any service operation you must be familiar with the NEM-4 product and module
level architecture. You have to also be familiar with the NEM-4 specified service tools
such as the Phoenix service software, flashing tools and software.

General guidelines for NEM-4 trouble shooting

Tools needed for Troubleshooting

• Service tools (as listed at service tools chapter in service manual)
• Laboratory power supply with current indicator
• Oscilloscope
• Digital multimeter ...

General guidelines

If the device cannot be turned on by any means, see "dead device" trouble shooting
Current consumption (missing consumption) gives an idea whether the device is able to
start up.
Dropping supply voltage or very large current consumption indicates a short circuit
Check whether the connection with Phoenix works and what can be discovered with
Phoenix (ADC-readings, baseband selftest, bb-calibrations etc.)
Check baseband selftests with Phoenix if "CONTACT SERVICE" is shown on the display.
Check visually display and rocker faults
Force phone to LOCAL mode and make keyboard test by phoenix
Check that board-to-board connector is OK, and connectors make good contacts.
If liquid damage, stop repairing!
Flash phone before disassembling it if fault is not obvious and Phoenix connection is OK.
Disassemble phone:
Check failed module visually:
Mechanical damages?
Issue 1 09/2003
Company Confidential
Copyright  2003 Nokia Corporation
Company Confidential
NEM-4
BB Troubleshooting
Page 6(a)-3