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Macbook A2338 No Display ; Suspected Sensor Issue

Instafixx

Instafixx

Member
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 ?
 
Instafixx

Instafixx

Member
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

Instafixx

Member
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 ?
 
Instafixx

Instafixx

Member
Yes both working - Checked using external monitor.

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

Instafixx

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

Instafixx

Member
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 ?
 
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Instafixx

Instafixx

Member
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

2informaticos

Administrator
Staff member
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

Instafixx

Member
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
 
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