820-2936 - Corroded LVDS connecter. No image after replacing.

[gcain]

The LVDS connecter was burnt out and corroded through. I have replaced it twice.

Laptops chimes and works on external display. It gives me a backlight and thin white line down the bottom. Like the image has been compressed into a 2px high line. It is also doing a scan effect with the backlight. Hard to explain and I can't get a picture of it.

Customer is losing his mind over this one. :/
But I just can't seem to get the picture back.

 

[dukefawks]

Tried a known good LCD/Cable?

 

[gcain]

My shop test screen just gives a backlight with no picture.

I have never worked out the compatibility between MLB though. A screen off a 3115 would work on a 2936?

 

[aprendiz]

Yeah.......

 

[gcain]

In diode mode;
L9080::2 = 0.03

Is that right?

 

[jadao]

No thats doesn't look right.
did you put a 2012 lcd in 820-2936?
it s same pinout but diferent connectors...
there is a little gap when you insert the lvds it s easy to short with neighbor pins...
last time I did that L9004 burned because pin 2 lvds touched pin 1 on connector.

 

[gcain]

L9004 seems to measure okay.

Will replace L9080 in the mean time, can I replace it with an L9080 from 2530?
All my 2936s are missing their L9080s already.

 

[gcain]

Replaced L9080, still getting the 0.03 in diodemode on Pin 2.

 

[jadao]

0.03 in diode mode with red probe on ground and black probe on pin2 L9080 is low, its a short to ground.
L9080 can't be the reason because it doesnt provide internally a path to gnd.
L9080 is bad when you don't have continuity between pins 2 & 3 or/and 1 & 4.

When you removed L9080 did you check witch side 0.03 was showing? On pin 2 or pin 3?

Most likely short is coming from lvds J9000 connector. Inspect pin 18 and 19 on j9000.

 

[gcain]

Thanks Jadao,

Just before I saw your post I was starting to think it might be the LVDS jack causing a short. There really isn't anything else.

I'll replace it in the morning and report back.

 

[dukefawks]

If the short come from LCD connector it is usually a full short. I suspect a bad PCH. Remove L9080 and see on which side the short is, I bet the PCH.