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29.3 Check EEProm
Open the phone and check for liquid damages.
No further action should be taken for a liquid damaged telephone.
Check the soldering at D600 pin 3, 4.
Check R619, R620.
Make sure there is no short circuit against ground at I2CCLK or I2CDAT.
Give the board power and check VDIG +3.2 V
Sometimes it can help to replace D600.
29.4 Check Speech DSP (Speech coding)
Dismount the phone and check for liquid damages.
No further action should be taken for a liquid damaged telephone.
Give the board power and check VDIG +3.2 V
If the voltages are correct, replace D900 or D600.
29.5 Check AASIC (Analogue ASIC)
Open the phone and check for liquid damages.
No further action should be taken for a liquid damaged telephone.
Give the board power and check VDIG +3.2 V
Measure VTRACK on N450 pin 2 +0.75 V
If the voltage is lower, replace N450 and perform a new selftest.
Sometimes there is a short circuit against ground on the VTRACK-input on N800.
Measure the resistance at C850, C851, C853 and C833 and compare with a reference board.
If the voltage is correct, replace N800.
If that did not make it, replace D600.
29.6 Check RTC (Real time clock)
Open the phone and check for liquid damages.
No further action should be taken for a liquid damaged telephone.
Give the board power and check VDIG +3.2 V
Check on B600 to se if it oscillate 32.76 kHz.
The signals amplitude is to low for most frequency counters to measure.
Some oscilloscope has such a high impact on the signal that it can be lost.
Mainly it is B600 that is faulty, but sometimes it is C690, C691 or D600.
4/00021-3/FEA 209 544/18 B
Trouble Shooting Guide, Advanced
.
DC
, VDSP +3.2 V
DC
DC
and R703.
DC
at +4.8 V
VBATT.
DC
DC
and VRTC +3 V
DC
DC
and VDSPC +2.5 V
.
DC
.
117(121)
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