Macbook A2338 No Display ; Suspected Sensor Issue

[Instafixx]

The device was water spilled on the keyboard . Replaced the keyboard and all was working fine for 5-6 days.
Then it suddenly became a no display issue. Tried another Display but same.

Strangely i get the touchbar display but there is no Caps Lock Light. I get external display too.
Without display connected as well i dont get caps lock light - which is weird. I think the Sleep/Wake sensor is malfunctioning and the device is in Sleep State.
Is my observation correct? How can we solve this ?

 

[2informaticos]

Check UR200 signals.

 

[Instafixx]

AMR_RIGHT_OR_ND_1V8 is low at 1.5V ( All flex disconnected).

Should we force this signal by 100-10K resistor instead of 1M ( in place of RR201)

 

[Instafixx]

Replaced RR201 with another Resistor. Issue Solved.

 

[Instafixx]

Hi,
Its back to the same again.

UR200 Signals are fine.

AMR_RIGHT_OR_ND_1V8 is 1.76V
IPD_LID_OPEN_R_1V8 is 1.79V
AMR_LEFT_OR_ND_1V8 is 1.79V

What else can be the issue ?

 

[2informaticos]

Do you get internal video disconnecting JT200/400?

 

[Instafixx]

No. I checked with Only TCon and Charging Port Connected

 

[Instafixx]

hello, kindly reply?

 

[2informaticos]

KB/TP still not working?
Check them using external monitor.

 

[Instafixx]

Yes both working - Checked using external monitor.

I replaced RR201 again with another 100K Resistor - Just in case, It still the same.

 

[2informaticos]

There is no lid sensor problem.

Test the machine with audio board disconnected.

 

[Instafixx]

I mentioned earlier too that i have tested with just the Display connected and the charger connected.
Still no image

 

[2informaticos]

Do you get image, only missing backlight?
Check LPDP_INT_HPD level.

 

[Instafixx]

No Image. No backlight.

LPDP_HPD_INT is 0V.
Diode Mode to Ground is .375
Resistance Across Pins of RP611 is 30 K Ohms and 20 kOhms ( Values when swapping the probes across pins)

UPDATE - Tried with another Tcon Flex - No Change

With TCon Board Disconnected
Resistance Across Pins of RP611 is 46K.

RP611 is a 47K Resistor after all.

Also if you are ruling out the sensor issue then why isnt the Caps Lock Light toggling ?

 

[2informaticos]

You've said KB/TP are working...

 

[Instafixx]

Let me check again and revert

 

[Instafixx]

Everything Connected. On External Display - KP/TP are working but there is no Caps Key Light - although the Caps Lock is working too.

The sensor is also working. When i close the LID - get the password screen on my external monitor and when i open the LID it goes to the secondary display. Hence the LID Sensors are fine.

One More Finding - If i am disconnecting the Display - the LID Sensors are still functioning the same way as they work when the Display is connected.

 

[2informaticos]

Caps Lock LED is driven by UT105.

CPU requires high level on LPDP_INT_HPD, to detect internal LCD.
This signal comes from T-CON board.
3V3_SW_LCD_CONN must appear first.

 

[Instafixx]

3V3_SW_LCD_CONN is 0V.

is A2337 eDP Flex is compatible with A2338 ? i had checked with A2337 flex and still had no internal display

 

[2informaticos]

You can't expect image on a non powered display!
Check UP701 voltages.