User Guide

NSB-5

Troubleshooting Instructions PAMS Technical Documentation

Page 20 Nokia Mobile Phones Ltd. Issue 1 03/01

Audio failure: Uplink (microphone) and downlink (earphone) are broken

Figure 14: Fault Finding for Broken Uplink and Downlink Audio

Uplink and downlink are

broken

Voltage over C113

(HOOKDET) is 2.8V without

external audio devices

Check R113, R112, C113,

C176

Voltage over C110

(HEADDET) is 2.8V without

external audio devices

Yes

Check R110, R109, R108,

C110

Frequency at E501 (PCMSclk)

is 8kHz square wave logical

level during call

Yes

Check N200

Check for uplink and for

downlink broken

Yes