Vizio VX42L HDTV10A Service Manual page 91

TROUBLE OF DC-DC CONVERTER
CONFIDENTIAL – DO NOT COPY
Start
J1 PIN10,11,12
Yes
J1 PIN 2,3,4,5
Yes
U1 pin 5 6 7 8
Yes
U2, U4 & U33 pin2
Yes
U6 pin 2
Yes
U5 pin2
Yes
U10 pin2
U3 pin1 & pin2
END
N0
The voltage is about + 5V
1. Check power board
2. Check power cable, F2 & connection J1
3. Check U8 pin1 (+5V) & pin2 (+3.3V)
N0
The voltage is about + 12V while power switch on
1. Is J1 connection good
2. Check J1 Pin1 is up to about 3.3V?
3. Check power board
4. Check F1.
N0
The voltage is about +5V while power switch on
1. Check F2 & U1
2. Check OPWRSB (R20)
3. Check U1 pin1&2 or pin 3&4, should have -1V more.
N0
The voltage is about +3.3V
1. Check F2 & U1
2. Check U2, U4 & U33
N0
The voltage is about +1.8V
1. Check F2 & U1
2. Check U6
N0
The voltage is about +1.2V while power switch on
1. Check F2 & U1
2. Check U5
N0
The voltage is about +2.6V while power switch on
1.Check J1 Connect
2.Check U10
The voltage is about +12V to +5V(for Tuner)while
power switch on
1. Check F1
2. Check U3 pin1 (+12V) & U3 pin2 (+5V)
Page 9-5
File No. SG-0211