6-6
3. Checking the Back Light Unit
Is +19V supplied to F301 pin 1?
OK
NG
Failure point
Printed wire broke between P312 pin 1.
Check the BKLT_EN signal of the rectangle input I327 pin 3 at TTL high level
OK
NG
Is a "H" level being output in the TTL level from I306 pin
14 Or, is BKLT_EN signal of the rectangle being output?
NG
Failure point
Printed wire broke between
I306 pin 14 and I327 pin 3.
Check the PWM signal of the input from I315 pin M4 (R374 pin 2) is a PWM signal.
OK
NG
Failure point
1) Printed wire broke between
I315 pin M4 and R374 pin 2.
2) I315 failure.
Failure point
1) Inverter cable disconnection.
2) Inverter of LCD module failure.
Is connected AC adapters operating normally?
OK
NG
Failure point
AC adapter needs to be
changed to a normally
operating unit.
Failure point
Inverter cable disconnection.
Is +19V supplied to P308 pins 3,
4 to inverter PWB?
OK
NG