Nokia NHM-7 series Service Manual page 139

PAMS Technical Documentation
Display
faults 2
Are the display
led's turned on ?
Yes
Display
faults 3
Issue 1 10/2001
No
Measure signal
fromV301 pin. 3.
Is it 128 Hz
~3.3Vp–p ?
No
Measure VBATT
from V301 pin. 4
It is OK?
Yes
Measure
PWM LED's
control signal from UEM
Is it 128 Hz
~3.8Vp–p ?
Yes
E Nokia Corporation
Troubleshooting Instructions
Yes
No
No
NHM–7
Check LED's
and line
Check R307
and VBATT
line
Check control
signal line.
If OK,
Change UEM
Check R305,
V301, V329
and line
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