Phone Does Not Register Onto The Network, Or The Phone Cannot Make A Call - Nokia NHM-8NX Series Troubleshooting Instructions

PAMS Technical Documentation

Phone does not register onto the network, or the phone cannot make a call

If the phone doesn't register to the network, the fault can be in either BB or RF. Only few
signals can be tested since several signals is 'burried' in one or more of the inner layers of
the PWB.
First of all check that SIM LOCK is not causing the error by using a Test-SIM card and
connect the phone to a tester.
Issue 1 05/02
Phone do not register to
network
or phone cannot make a call
C222, C233, C224, C225,
C226, C227
Voltage = ~2,78VDC
All during GSM frame-
call mode.
Use TXP on C646 as trigger
Yes
C230, C231
Voltage = ~1,35VDC
All during GSM frame (call mode)
Use TXP on C646 as trigger
Yes
J608, J609, J610
Check RF serial bus during
GSM-frame :
Logic HIGH = 1,8VDC
Logic LOW = 0VDC
RFBUSCLK (J608),
RFBUSDA (J609),
RFBUSEN1X (J610)
Yes
R601, R603
Check analog signals during
GSM-frame (RX slot):
RXIP/N (R601) = 0-1,45VDC
RXQP/N (R603) = 0-1,45VDC
Yes
R610, R611
Check analog signals during
GSM-frame (TX slot):
TXIP/N (R610) = 1-1,75VDC
TXQP/N (R611) = 1-1,75VDC
Yes
Check RF
ãNokia Corporation
Troubleshooting Instructions
Check :
C222,C223, C224, C225,
No
C226, C227, PWB.
Else defective D200 or D400*
Check :
C230, C231, PWB.
No
Else defective
D200* or D400*
Check :
PWB.
No
Else defective D200*
or D400*
Check :
PWB.
No
Else defective D200*
or D400*
Check :
R610, R611,PWB.
No
Else defective D200*
or D400*
NHM-8NX
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