Nokia 5110 Manual Do Serviço
PAMS
Technical Documentation
NSE–1
Disassembly & Troubleshooting Instructions
Page 10
Original 03/98
Power doesn’t stay on, or phone is jammed
If this kind of fault has come after flash programming, there are most
probably open pins in ICs.
The soldered joints of ICs: D200 (MAD2), D210 (FLASH), N100
(CCONT), D221 (SRAM) are useful to check at first.
probably open pins in ICs.
The soldered joints of ICs: D200 (MAD2), D210 (FLASH), N100
(CCONT), D221 (SRAM) are useful to check at first.
Normally the power will be switched of by CCONT (N100) after 30 se-
conds, if the watchdog of the CCONT can not be served by software.
The watchdog updating can be seen by oscilloscope at pin 50 (DataselX)
of CCONT.
In normal case there is a short pulse from ”1” –> 0 every 8 seconds.
conds, if the watchdog of the CCONT can not be served by software.
The watchdog updating can be seen by oscilloscope at pin 50 (DataselX)
of CCONT.
In normal case there is a short pulse from ”1” –> 0 every 8 seconds.
The power off function of CCONT can be prevented by connecting a short
circuit wire from CCONT pin 29 to ground.
circuit wire from CCONT pin 29 to ground.
Power doesn’t stay on or phone is jammed
EEPROM (D240) pin 8 (VBB) 2.8 V
J522 (VXO) 2.8 V
NO
YES
J227 master reset (Purx) = ”1” (2.8 V)
NO
J228 sleep clock(SCLK)
square wave 32 kHz
NO
YES
Faulty circuit N100
or over loaded PurX line
check sleep
clock circuitry
(B100, R154...)
YES
MAD2 (D200) pin 93: 13 MHz sine wave
clock signal: 500 mVpp min.
YES
NO
J506 (RFC) 13 MHz
800 mV min
YES
check C213, R213
NO
check buffer V705 and
VCXO G600
YES
connect the shortcircuit fire from N100 pin 29 to ground (watchdog)
N100 is faulty
OK
VBAT is correct
3.6 V
YES
CCONT watchdog is served?
(pin 50 pulses 1 –> 0)
NO
YES
software is able to run
check UI module
after few seconds, check
BSI and BTEM lines
If power is switched off
Open pins or faulty circuit:
D200, D210, D221, N100
R215