820-01521-02

[Sr. Robot]

Hi, got an 820-01521-02 machine that boots up (cap lock has green light, keyboard has backlight and the machine has sound). The display has backlight but no image.

SCM and PRAM reset did nothing. It also doesn't seem to detect external monitor. Board is intact and LCD cable seems undamaged.

 

[2informaticos]

Force external video disconnecting internal LCD.

Any history available?
Did you check diode mode to ground on EDP_INT data lines?

 

[Sr. Robot]

Disconnected LCD but still not detecting external monitor.

Client says one day he turned it on and it had no image.

Mode to ground on DP_INT lines is over 0.250 on all of them

 

[2informaticos]

Do you get almost same value on each pair???
You may get difference between pairs, but should get almost same reading for both lines of a pair.

 

[Sr. Robot]

Yes, i get almost same value between all of them. from 0.258 to 0.262

 

[2informaticos]

Then must be bad CPU; damaged iGPU...