Trouble Shooting Guide, Advanced
4/00021-3/FEA 209 544/25 C
Ericsson Mobile Communications AB
7(78)
2.3
The phone can not be programmed
Make sure that:
The battery connector not is mechanically or liquid damaged.
The system connector not is dirty, mechanically or liquid damaged.
Replace it if necessary.
No further action should be taken for a liquid damaged unit, send it on according to the
local company directives.
Attach a “dummy battery”. If the phone consumes current immediately, the fault usually
depends on a short circuit of VBATT.
Start the phone with the On/Off button and check the current consumption.
If the phone consumes no current at all when the button is pressed, there probably is
liquid damage. Open the phone and check for liquid damage.
Check the keypads for dirt, mechanically or liquid damage and clean them it if necessary.
If the phone consume more than 30 mA, go to section 2.4.3.
If the phone does not start, try to program it.
If the phone does not start in the flash programmer, go to section 2.4.1.
If the phone can be programmed, but does not start afterwards or is troublesome in the flash
programmer, go to section 2.4.2.
If the phone starts after programming, there is probably no fault, but to eliminate the
possibility of intermittent faults check for bad soldering on the card.
2.4
Measuring at a powered circuit board
2.4.1
Does not start in the flash programmer
Make sure the system connector pads not are mechanically or liquid damaged.
No further action should be taken for liquid a damaged unit, send it on according to the
local company directives.
Attach the board to the fixture and connect the battery voltage and the programming interface.
Check VPPFLASH at X800 pin 3.
The voltage will not be switched on until you have started the phone in the EMMA II-flash,
after the message “TURN ON THE PHONE TO START”.
If the measurements are incorrect the fault is probably found in the test equipment.
Measure the voltages VDIG and VCORE.DSP.
If VDIG is to low, the fault is due to N700.
If VCORE.DSP is too low, change N720, C722 and R732.
If the fault still remains, it is probably due to N700.