Repair Flow Chart - Philips M38 107B4 Service Manual

A. Power Supply Failure
1. Symptom :
no startup sound
LED light off
2. Symptom :
hiccup mode with
startup sound or
blinking LED
3. Symptom:
abnormal sound

Repair Flow Chart

check 7105 pin8
140V<pin8<360V
NO
replace 7105
replace 7105
Turn power off
check the resistance for
all output voltages+188,
78,13,-13,+6.3,+5,+8 V
check 6148,6155
6151~6153 short?
check 7153 pin3
Ok
voltage dip
check
+5V loading current
check
frequency Ok
F=30KHz~80KHz
check 7105
pin 1=11V
NO
check
1101/6102/
7101
OCP possibly active
check 3115,3113,
3119,6106,3123
check 7153 pin1
7.5V< pin1 < 8V
No
check
6160/3160/7154
3153/7155/2165
check 7101
drain waveform No
right?
Ok
replace 5101
M38 107B4
9
Go to cover page
check 7105
Ok
Pin6 output ?
Ok
check
6108/3125/
3111/7101
check 7105
pin 5
No
OK
replace 5101
Ok
check CPU pin 20
and 7805 emitter
check
6103/3104/
2110/3112
45
NO