820-3435 no backlight

[Kyle93]

Turns on but no backlight. Backlight fuse keeps getting shorted. Replaced fuse, Q7706 and Q7007 at same time but same thing happens.

Should U7701 be replaced next?

 

[2informaticos]

Did you check for short, or improper low value, on backlight rail before applying power?
Check w/ and w/o LCD connected; starting from fuse to LCD connector.

 

[JohnB8812]

Why didn't you check for a short...lol. Check for short with and without LCD connected as 2informaticos suggested on BKLT output.

 

[Kyle93]

.572 without LCD and 0.0001 with LCD.

Bad LCD?

 

[JohnB8812]

Either bad LCD connector on the board, bad LCD cable or bad LCD itself.

 

[Kyle93]

Found known good LCD to test with and short is gone but still no backlight. Replaced F7701 again but only 8.5V on PPVIN_S0SW_LCDBKLFET. Bad U7701? Board is spotless

 

[JohnB8812]

Most likely if only 8 volts.

 

[2informaticos]

Are you sure to get compatible screen?
Do you get image?