Checking The Back Light Unit - Elo TouchSystems ET17 XXL Series Service Manual

3. Checking the back light unit

Is +12V or +19V supplied to
NG
OK
Is +12V or +19V supplied to
P004(power BD) pin 1,2 to
inverter PWB?
NG
OK
Check the BKLT_EN signal of the rectangle input R360 pin 1 at TTL high level
NG
OK
Check the PWM signal of the input from I303 pin40 (R362 pin 2) is a PWM signal.
NG
OK
Failure point
(1) Inverter cable disconnection.
(2) Inverter of LCD module failure.
Are connected AC adapters normal goods?
Failure point
Inverter cable
disconnection.
Is a "H" level BKLT_EN signal being output in the TTL level
from I303 pin 114 rectangle output?
Failure point
(1) Printed wire broke between I303
pin 114 and R360 pin 1.
Failure point
(1) Printed wire broke between
I303 pin40 and R362 pin 2.
(2) I303 failure .
-
54
NG
OK
Failure point
Printed wire broke between
P001(power BD) pin 1.
NG
-
Failure point
An AC adapter is
changed to the normal
goods.