Nokia NSW-5 Series Service Manual page 223

PAMS Technical Documentation
1. Phone is totally dead
Phone does not consume current at all when the power switch is pressed,
or when the watchdog disable (J150) is grounded.
Battery voltage must be higher than 3.0 V. Otherwise CCONT prevents
power–on.
Phone is totally dead
YES
VBAT is 3.6 V at R153
YES
Voltage at J150 of CCONT
(N150) is 3.6 V
YES
C166 (VBB) 2.8 V
C158 (VR1) 2.8 V
when PWR switch is pressed
or watchdog disable pin is grounded
YES
See section: Power Doesn't Stay On
Figure 1. Troubleshooting diagram for a totally dead phone
Issue 1 10/00
Disassembly and Troubleshooting Instructions
Failure in VBAT line
NO
Check X105, X104, Z100, C100, C101
NO
Faulty circuit N150
CCONT (N150) J150 0V when
NO
PWR switch is pressed or
watchdog disable pin is (X101 pin
11) grounded
YES
Faulty circuit N150
E Nokia Mobile Phones Ltd.
NSW-5
Check R164, PWR switch,
NO
connector X300
Check watchdog disable
line to X101
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