A1706 820-00239-09 No Backlight

[iFix]

Hi Guys.

I have a A1706 820-00239-09 board no backlight. No liquid damage just stopped. I'm missing EDP_BKLT_EN, voltage present on R8400 contacts 1,2,4.

Q8400 pin 4 13v, pin 3 13v and others no present PPVIN_S0SW_LCDBKLT which also means PPVIN_SW_LCDBKLT_SW not present.

Any ideas?

Thanks

 

[2informaticos]

First confirm if you get image on internal LCD.
If not present, check external video at least.

 

[iFix]

Yes there's an image

 

[2informaticos]

No pulse at all at EDP_BKLT_EN, at the moment when the image appears?
Try another compatible LCD assembly.

 

[iFix]

EDP_BKLT_EN present all the time when lcd is connected. LCDBKLT_SW is missing going to Q8401 all other on mosfet are present

 

[iFix]

It was playing with the voltages but last time when i measured and saw LCDBKLT_SW is missing i resoldered U8400 and solved the issue

 

[2informaticos]

Glad to hear is solved.

For the future, post accurate info please; you've mentioned in the first post no EDP_BKLT_EN present...

 

[iFix]

Understood Thanks