Dell G3 3590 MB: 18839-1 No video

[javieromex]

Hello guys,

This laptop arrived from another shop, it had shorted the 19v line due to a PWR_CORE_PH1 shorted mosfet, I replaced the mosfet and the computer turned on without video, suddenly the PCH died!! (3V shorted to ground) I replaced the PCH and the computer is turning on again but NO VIDEO!

Currently:
-System diagnostic lights blinking: 2,7 (indicates LCD Failure).
-Caps Locks and ctrl+alt+delete respond.
-Tested 3 different BIN files (Also 1 clear ME)
-Tested 2 known good LCDs

-DCBATOUT_LCD: 19.V
-3D3V_LCDVDD_S0: 3.3V
-EDP_HPD_CONN: 2.5V

Find attached schematics and BV.

Any suggestion? (I have not checked with another LCD flex cable, its a bit expensive...)

Thanks

[mcplslg123]

Re: Dell G3 3590 MB: 18839-1 No video

Display works on HDMI?

[Sephir0th]

Re: Dell G3 3590 MB: 18839-1 No video

Have differentiated between "no Picture" and "no backlight" already?

[mcplslg123]

Re: Dell G3 3590 MB: 18839-1 No video

The Op claims caps lock and ctrl-alt-del works. So i assume its posting. Am i wrong@sephir0th?

[Sephir0th]

Re: Dell G3 3590 MB: 18839-1 No video

Of course you're right.

Backlight Control Signals are not in the list of the OP so i just want to rule that out.

if it wouldn't succesful does the P.O.S.T. there would be no point to look for Backlight of course.

[javieromex]

Re: Dell G3 3590 MB: 18839-1 No video

Of course you're right.

Backlight Control Signals are not in the list of the OP so i just want to rule that out.

if it wouldn't succesful does the P.O.S.T. there would be no point to look for Backlight of course.

Hello. I know difference between no backlight and no picture. I have no picture.

Not picture on HDMI either.

[javieromex]

Re: Dell G3 3590 MB: 18839-1 No video

Display works on HDMI?

No, not picture on HDMI either.

[mcplslg123]

Re: Dell G3 3590 MB: 18839-1 No video

No, not picture on HDMI either.

In some cases, if internal flex cable is inserted in mb, then hdmi dont work. make sure you disconnect intenal flex cable and screen and try again on hdmi.If already disconnected, just ignore this message.

[javieromex]

Re: Dell G3 3590 MB: 18839-1 No video

In some cases, if internal flex cable is inserted in mb, then hdmi dont work. make sure you disconnect intenal flex cable and screen and try again on hdmi.If already disconnected, just ignore this message.

Yes, I tested with flex cable disconnected and same...

Any other suggestion?

[fighter158]

I have same issue and U5501 is shorted from pin 5 to pin 1. IC SY6288C20AAC