User Guide

PAMS
Technical Documentation
NSE–8/9
Troubleshooting
Page 5
Issue 1 07/99
4.1. Phone is totally dead
This means that the phone doesn’t take current at all when the power switch S416 is
pressed or when the watchdog disable pin (X201 pin 11) is grounded. Used battery
voltage must be higher than 1,9 V. Otherwise the hardware of the switcher V105 and
CCONT (N100) will not operate reliable.
Phone is totally dead.
Measure Vb voltage at
C115
> 1,9 V
Measure Vdc_out
voltage
at Vibra pad E103
> 3.1V
Power doesn’t stay on.
No
Yes
Yes
No
Failure in VB.
Check X101, X102 and
Jig or tester
Measure ”PWRON” voltage at R413
when pwr–switch (S416) is pressed or
WDDIS is grounded
(R424 connected to gnd).
Voltage less than 0,5V
(Will be low only during
power–up of CCONT
if power switch
is pressed.)
Measure voltage at
2,85v>C117 (Vbb) > 2.7V
2,85V >C102 (VXO) > 2.7V
When PWR switch is pressed or
WDOGDISABLE is grounded.
Voltages OK?
No
Yes
Check R413, V410, S416, R423
N100
Check WDDIS line
Yes
No
Switcher
Faulty:
– PCB
– N100 circuit
– 32KHz or RFclk osc.
– Row0 on MAD
– Insufficient supply
capability of V105 circuit
Figure 4–1