General - Sony Ericsson K790 Troubleshooting Manual

1 General

The purpose of this document is to indicate the electrical level repair actions associated with the different
failure symptoms.
For symptoms that have multiple repair actions, the repair actions are listed in order of their probability of
creating a successful repair. The first action has the highest probability, and subsequent actions have lower
probabilities. The intention is for the repair technician to implement the first repair action and then retest the
phone. If the phone continues to fail the same test, then the technician should continue to the second repair
action. If the phone continues to fail the same test after all of the repair actions are exhausted, then the
phone will be considered not reparable at this level. This document should be used only after the actions
from the Mechanical Trouble Shooting Guide have been exhausted for the specific symptom.
Voltage, current, and resistance information is provided for some symptoms to enable faster repairs.
Perform current measurements using a dummy battery and power supply with digital current display. The
phone should be fully assembled. Perform voltage and resistance measurements with a multimeter.
Purchasing this equipment and performing these measurements is optional but recommended.
4/000 21-2/FEA 209 544/112 C
©
Company Internal Sony Ericsson Mobile Communications AB
Trouble Shooting Guide, Electrical
Perform current measurements using a dummy
battery and power supply with digital current
display. The phone should be fully assembled.
Perform voltage measurements with a multimeter.
Perform resistance measurements with a
multimeter.
2(6)