5.Troubleshooting (continued)

5.2Nothing displays on the screen (Screen is black and colour of LED is blue)continued

ACER X193HQ

 

21

 

 

 

Go to cover page

Continue

Check the 5V power supply for

P305 pin 1,2,3.

NG

Check the I301 pin2 if voltage is 3.3V

OK

Check the I309 pin2 if voltage is 1.8V

NG

NG

Proceed "Checking the DC/DC converter

circuit" section.

Proceed "Checking the DC/DC converter

circuit" section.

OK

OK

Check the I307 pin2 if voltage is 5V

OK

Failure Point

NG 1) FB312 is open.

2) C353, C355 is short.

Check if the voltage

between I307 pin2 and

pin3 is above -0.7V

NG

OK

Failure Point

I307 is failure.

Check the input voltage level whether was changed when pressed function keys on the P304 pin 5 (normal is high level, when push buttom, generated 2.2V/1.9V/0.7V)

NG

Check if the Q311 pin2 of

 

 

 

 

 

 

PANEL Power_ON/OFF

 

 

 

 

Failure Point

 

NG

 

signal that outputted by I305

 

 

 

1)

Printer wire between R411

 

 

 

 

pin10 is High level.

 

 

 

 

 

and I305 pin10 is failure

 

 

 

 

 

 

 

 

2)

I305 is failure.

 

 

 

 

 

 

 

 

3)

R413,C366 is short

 

OK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Failure Point

1)Printed wire between R311 pin3, R410, R412, I307 pin1 is failure..

2)Q311 is failure.

Check if the voltage on I305 pin 20 that is

from 3.3V to 0.7V.

OK

Check the P305 all LVDS signals.

NG

OK

Failure Point

1)The LVDS cable broke between P305 and LCD module.

2)LCD module is failure.

NG

OK

Failure Point

I305 is failure

Failure Point

1)Printed wire broke between P305 and I305 LVDS signals.

2)I305 is failure.

Failure Point

1)Printed wire broke between P304 pin 5 and I305 pin 20.

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Acer RA19WAANU service manual Circuit section