A2338 - Liquid damage to EDP

[joesklar]

Hi,

I've got a MacBook that had liquid damage/corrosion only limited to the EDP connector for the LCD. The corrosion was only on the TCON board (I think it's called that) and the cable. The connector on the logic board side was not damaged. I replaced the flex cable and EDP connector on the TCON board. I still have no image/backlight.

The computer boots and has external display output.

I noticed that all my diode mode readings along the bottom pins of the connector on the TCON board return O.L.

I have a feeling a known-good LCD will be advised to test. But is there anything else I can check?
Also does this screen replacement require chip swap/angle sensor calibration or can I just swap the entire assembly?

Thanks!

 

[2informaticos]

"I noticed that all my diode mode readings along the bottom pins of the connector on the TCON board return O.L."
This model has series capacitors for data lines.
If you want to make an idea about these lines, you should check on "left" side of these caps, reffering to schematic.

Check on T-CON board the levels for 5V_SW_LCD, LPDP_INT_HPD and EDP_PANEL_1V8_EN.

BTW, camera works?

 

[joesklar]

Hola,

Thanks for the suggestions.

I checked all of the "left" capacitors for the signal line. Diode mode readings return the same value on pin 1 for all (0.384). Pins 2 are O.L.

I don't have any schematic for the TCON board, so I tested those signals on the logic board with the LCD connected. Is this suitable?

PPV5_SW_LCD - 0.530 - 5.165V

LPDP_INT_HPD - 0.342 - 0V

EDP_PANEL_1V8_EN - 0.648 - 1.8V

I have not yet set up the laptop, so the webcam has not been tested. I will report back on this.
Many thanks

 

[joesklar]

The webcam doesn't appear to work. The green LED turns on and off periodically. Approx 15 seconds on, 2 seconds off, cycling.
Sorry I'm a novice so I had some trouble transferring the main display to external. On boot the secondary display was just a blurry image. I had to close the laptop lid and then connect a keyboard/mouse to use the system. Is there any keyboard shortcut that can perform this action?

 

[2informaticos]

Seems to have a problem with internal LCD.
It should send HPD signal to M1 CPU.
You may have problems with T-CON's electronics, or LCD itself.

Try Command + F1 keys combination...

macbook shortcut key enable external video - Google Search

 

[joesklar]

Thanks. I guess the initial corrosion is more widespread up to the LCD...
Back to my previous question: does this screen replacement require chip swap/angle sensor calibration or can I just swap the entire assembly?

 

[2informaticos]

You can replace entire LCD assembly without problems.