Nokia RH-18 - DC Characteristics; Supply Voltage Ranges

CCS Technical Documentation
Company confidential RH-18/36/38
Issue 1 10/03 Nokia Corporation. Page 13
Audio related faults 1: Earpiece and microphone
Figure 9: Top: Earpiece troubleshooting, bottom: Microphone troubleshooting
Earpiece do not work
Check :
R386, PWB.
Else defective D200*
No
Defective D200*
Z150, R161
Check Z150, R161 is
working correctly
(no short/open-circuit)
Replace :
Earpiece
Yes
Error still present
Microphone do not work and
the isn't any mechanical
problem
Check :
R165, C168, PWB.
Else defctive D200*
No
Error still present
R165
Check voltage level on
R165 towards UEM (bias)
= 2,1V
Replace :
Z100
Yes
Replace :
System Connoctor
Z100
Check Z100 is
working correctly
(no short/open-circuit)
No
R153
Check voltage level on
R153 towards mic-lines (bias)
= 1,0V - 1,4V
Check :
R153, R157,C151, C152,
C153, C154, PWB.
No