A1932 boot problem

[leemobile2306]

Hi
I have in for repair a very confusing a1932 late 2018 MacBook Air board number 820-01521-a
The device will not boot in to operating system just freezes on the progress bar with the fan spinning on high but the board is not getting hot.
Tried new fan, trackpad and keyboard, new screen.
Getting 20v 0.200 on charger no shorts on the board no liquid anywhere.

Any help would be appreciated

Thanks

[cruiser_]

Re: A1932 boot problem

tried resetting PRAM/SMC?
if that fails, perhaps a DFU review would cure your issue

[reformatt]

Re: A1932 boot problem

Boot into diagnostics (D on startup) and report back. Fan running high speed usually means missing sensor data and the CPU is throttled to slowest speed.

[tech.mgr]

Re: A1932 boot problem

Boot into diagnostics (D on startup) and report back. Fan running high speed usually means missing sensor data and the CPU is throttled to slowest speed.

i have the same issue all is okay and booting normally but to slow performance
i try diagnostic and get noting all is okay

i try replace charging ic since my mac is not charging battery and give this notification in os (battery not charging)

ant suggestion .

thanks in advanced

[mon2]

Re: A1932 boot problem

Do a SMC bypass upon boot to check if the unit boots faster.

Is the battery a known good battery?

[tech.mgr]

Re: A1932 boot problem

Do a SMC bypass upon boot to check if the unit boots faster.

Is the battery a known good battery?

mac is not reading battery and when i plug it gives battery not charging

[mon2]

Re: A1932 boot problem

1) What is the history of the battery ? Is it a known good battery ?

2) Is the logic board # 820-01521-a ?

3) See attached.

Remove all power - no battery / no adapter.

Meter in resistance mode (start with the lowest scale).

Check the resistance to GROUND -> pin # 3 to ground; pin # 4 to ground of the battery connector.

We are checking for the status of the ESD diodes which are often used on the battery connector to protect the I2C / SMBUS communication lines. ESD transients often kill one or both of these diodes which will shunt the communication between the BMS module inside the battery back and the I2C / SMBUS bus master IC. Results in the battery not being detected.

This is assuming the connector itself is not faulty.

[tech.mgr]

Re: A1932 boot problem

1) What is the history of the battery ? Is it a known good battery ?

2) Is the logic board # 820-01521-a ?

3) See attached.

Remove all power - no battery / no adapter.

Meter in resistance mode (start with the lowest scale).

Check the resistance to GROUND -> pin # 3 to ground; pin # 4 to ground of the battery connector.

We are checking for the status of the ESD diodes which are often used on the battery connector to protect the I2C / SMBUS communication lines. ESD transients often kill one or both of these diodes which will shunt the communication between the BMS module inside the battery back and the I2C / SMBUS bus master IC. Results in the battery not being detected.

This is assuming the connector itself is not faulty.

i measure these lines and positive line all is okay ,knowing that without battery laptop have slow performance

[mon2]

Re: A1932 boot problem

Do post the requested answers and measurements. We cannot guess the values of your logic board.

Review the many questions above and answer each to move forward in the review.

A good battery is required:

https://www.badcaps.net/forum/showthread.php?t=99255

[tech.mgr]

Re: A1932 boot problem

Do post the requested answers and measurements. We cannot guess the values of your logic board.

Review the many questions above and answer each to move forward in the review.

A good battery is required:

https://www.badcaps.net/forum/showthread.php?t=99255

i try diagnostic and all is okay except battery not detected
you mean if mac powered on without battery then it will not works properly
and it will have slow performance

[tech.mgr]

Re: A1932 boot problem

Do post the requested answers and measurements. We cannot guess the values of your logic board.

Review the many questions above and answer each to move forward in the review.

A good battery is required:

https://www.badcaps.net/forum/showthread.php?t=99255

1) What is the history of the battery ? Is it a known good battery ? no idea i don't have original battery for test

2) Is the logic board # 820-01521-a ? yes

3) See attached. i check them already dear have good value

[mon2]

Re: A1932 boot problem

1) nothing was attached.

2) measure and post the voltage values on D6950 with the battery connected. Also attach the power adapter.