Troubleshooting
6-4
SF150T
6-2-1 No + 5 V
Y
N
N
output shorted ?
Start
N
Y
Y
N
Remove short
Y
Replace D4
Check PCB Pattern
Replace U2
Check CON 1
Check
U2 Input voltage
D4 Open or
Shorted ?
DC 6 V
Check U2 ?
End
6-2-2 No -12 V
Y
Y
N
N
output shorted ?
Start
N
Y
Y
N
Remove short
Replace D5
Check PCB Pattern
Replace U1
Check CON1
Check
U1 Input voltage
D5 Open or
Shorted ?
-15 VDC
U1 Output ?
End