820-00165A backlight issue

[2informaticos]

25V is the correct voltage there.
If drops, possibly corrosion under U7701, or surrounding resistors.

Just in case, did you test with known good screen?

 

[manumathew.017]

I have changed u7701 , still backlight is not staying …
I don’t have a working lcd to test… is there a way I can make sure the current lcd is good?

 

[2informaticos]

DP_INT_HPD is steady high?

 

[manumathew.017]

DP_INT_HPD is steady high?

It is steady and 2.681V

 

[2informaticos]

Did you check the basics?
XW7720 is OK?

 

[manumathew.017]

Yes Confirmed the continuity

 

[2informaticos]

BKL_EN/PWM both stable?
If all components are good, then bad LCD...