MacBook Air A1932 2019 No Sleep Mode

[Strolch]

Hi, i have a MacBook Air from 2019 A1932 it have bit liquid damage. the Mac is running fine, but if i close the Mac to sleep, the display will not go in standby. but if i go to the left corner to the Apple and click standby it will go to standby.

thx

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

Review the LID sensor which will be a hall effect switch.

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

Hi thx, where can I find the Lid sensor? thx

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

U4850?

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

What is the 820-xxxx marking on your logic board ?

Is it 820-01521 ?

For (A1932) 820-01521, the partial schematic is attached.

[SMDFlea]

Re: MacBook Air A1932 2019 No Sleep Mode

What is the 820-xxxx marking on your logic board ?

Is it 820-01521 ?

edit.sorry .

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

@SMDFlea, that is for a diffferent logic board.

[piernov]

Re: MacBook Air A1932 2019 No Sleep Mode

820-01521 is the only board found in A1932. Shematics already posted on the forum.

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

Baby the U4802 is damage? the board looks good around U4802

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

1) Close the lid and read the voltage with your meter (DC mode) on pin # 4 of U4802.

2) Open the lid and read the voltage with your meter on pin # 4 of U4802.

Post each value.

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

ok

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

Hello, can I measure at pin 32 of the J6700? it goes to pin 4 of the U4802. Because the U4802 is on the back of the logic board. thx

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

J6700

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

Yes. Highlight the net and find any easy to measure point. They are only common connections (traces) between the parts on the same net.

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

Hi,, i have 1,7965V open and same 1,7965V display close

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

Ok.

1) See attached. The lid logic is not working properly.

The OR gate @ U4802 is operating @ +1v8 so it is OK for the output pin # 4 = +1v8 = '1' (Logic HIGH) when the lid is OPEN.

When the lid is closed, pin # 4 of this single OR gate should be Logic LOW.

2) Next, let us check if the OR gate is receiving the proper signals upstream for the lid open / close.

Locate R4804 resistor and R4805 resistor which will be on the same side as the J6700 connector you just probed. These resistors are to the LEFT side of this connector.

They are tiny 0201 parts so probe with care.

Check the voltage on R4804, pin 1 when lid is closed. Then confirm the same voltage is present on pin 2 of R4804. Post the voltage when closed.

Check the voltage on R4805, pin 1 when lid is closed. Then confirm the same voltage is present on pin 2 of R4805. Post the voltage when closed.

For starters, you could probe J6700, pin # 1 = SMC_LID_LEFT

&

probe J6100 (on the same side of the PCB), pin # 27 = SMC_LID_RIGHT

What we wish to ideally see is that when the LID is CLOSED, both of these points should be logic LOW.

For the Dual-input OR gate to output a LOW, both inputs must be LOW.

Respectively, if the OR gate is stuck to HIGH then

either one of the inputs is stuck to HIGH OR (no pun)

the OR gate is defective. Personally we have seen single gate OR gates from Diodes Inc. being defective even though we purchased them from factory and in full tape & reels. Such a pain to desolder and fix so we switched suppliers for this component.

Post your voltage readings for the SMC_LID_RIGHT & SMC_LID_LEFT labels while the case is CLOSED.

Update - have a suspicion that since this single gate OR is near the edge of the PCB (bottom side from your connector you reviewed), at least one of the input signals is NOT making it to the gate due to corrosion. That is, the local pull-up resistors @ R4800 or R4801 are parking this OR gate to the fixed logic HIGH. Will know more once you probe the lid voltages.

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

Hi mon2,
i have 0V on R4804 pin1 and 0V on Pin2

i have 1,6267V R4805 on Pin1 and 1,6267V on Pin2

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

Ok.

What is the voltage reading on R4804 if the lid is OPEN ?

Does this resistor go to a logic HIGH value ~ +1v8 ?

[Strolch]

Re: MacBook Air A1932 2019 No Sleep Mode

hi, yes its 1,796.. V Pin 1 and Pin 2 on the R4804

[mon2]

Re: MacBook Air A1932 2019 No Sleep Mode

Do you have this logic board accessible to review the bottom side ?

1) Remove all power to the logic board. Meter in resistance mode (setting suitable to measure 10k ohms).

Confirm the resistance across R4805 -> is it about 10k ohms ? Compare to the resistance on R4804 as well.

2) Check the resistance from connector J6100, pin 27 (SMC_LID_RIGHT) to R4805, pin 1.

3) Check for possible corrosion on J6100 connector and mating cable - especially around pin 27. You can use a Q-tip and IPA (alcohol) to clean up the contacts if required.

What I believe is happening here is that the SMC_LID_RIGHT signal is not reaching this OR-gate. With the absence of this required signal, the local pull-up @ R4801 creates the fixed HIGH logic level. Then the OR gate outputs the static HIGH level and ignores the SMC_LID_LEFT. For the OR gate, as long as a single INPUT is HIGH '1', then the output level will be HIGH '1'. Respectively, BOTH inputs must be LOW '0' to output the '0' which is the proper logic level once the clamshell is CLOSED.