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dbrus12
07-03-2003, 11:37 AM
i have nokia 8210 that wont turn on
it worked fine until one not so fine day when i turn it on it stayed on for a few secunds and then go off itself
or only when i press numbers 1,2,3,..
i reball ccont and now i cant even turn it on.outgoing lines vxo,vref,vcobba,vrx have 3kohms to the ground(it should be over 10 kohms)
after pressing button on/off vrx,vtx,vsyn1 stay to 0 Volts and vsyn2 have 80mV
when i messure PURX on j227 it is 0.7V
other voltages are ok for about 10-15 secunds after pressing on/off button and then everything goes to 0 Volts

help,if somebody can please

do i need to flesh the phone after reballing ccont(i put the same ccont):confused:

alf
11-03-2003, 08:59 PM
march 12,2003

Hi there friend!
i may not be a proffesional but anyway try these procedure. Usually when a phone intermittently switches off or does not switch on, several reasons may be causing these problems.
1. try checking connector X101( I assume you have a layout diagram) IT MAY BE TWISTED OR BROKEN ...ETC.
2. Check pads on X101 on PCB if they are clean.
3. check CCONT (as i understand you already did) maybe you should try getting another CCONT or if not, make sure you have aligned the contacts very well and that all the balls are of the same size so that we are sure it is STILL NOT UNDERFILLED.
4. Check N505- the reference oscillator G830(26 MHz) is divided to 13 MHzsystem clock by HAGAR N505. Again reball if there are broken solderings.
hope these will help you with your 8210 problem.

alf

dbrus12
12-03-2003, 07:30 AM
could it be the reason that after changing ccont i didnt flash the phone