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LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
6. Trouble shooting
- 86 -
START
Check
"PWRON" signal of
TP1
2.0V
Check Combination
CN101 of Key PCB
when push the
power key
Check
"PWRON" signal of
TP1
0V
Check the
BACKUP Battery
Check Combination
CN101
or
Replace CN101
(Key PCB Connector)
Check solder
Q401
Yes
Yes
Yes
Yes
No
No
No
No
Connect power
supply to the DUT
Vbat = over 3.35V
Check the all LDOís
output
Is it correct?
Check solder whole LDO
parts or replace it
CN
CN101
01
Replace main PCB
Is the 26MHz
clock from
TP2
X101 of U104 ?
Check solder
Replace X-TAL
No
X1
X101
01
TP
TP1
Q401
Q401
TP
TP2
→
→
Summary of Contents for KC550
Page 1: ...Date May 2008 Issue 1 0 Service Manual Model KC550 Service Manual KC550 Internal Use Only ...
Page 182: ...Note ...
Page 183: ...Note ...