Macbook Air A1466 EMC 3178 Board 820-00165-A no power

[stellablu]

Hi everyone!

I'm working on a Macbook Air A1466 EMC 3178 Board 820-00165-A that doesn't power on. No liquid damage. No fan. I've tried various power adapter, no green nor orange light.

PPBUS_G3H is 8.18V, and from what I've read on other threads it seems that SMC is not communicating to the ISL chip, but I don't know what to do next.

Thanks in advance for help or advices.

[mon2]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Hi. See attached. Post the requested voltages.

Your case may be similar to another over the weekend. There is a one-wire circuit (Maxim / Dallas Semiconductor / now Analog) that communicates with the external adapter to light up either the green / orange or no LED status.

Confirm the contacts on the magsafe connector are clean - use alcohol.

Are you using an official adapter ?

Post the voltage on the one-wire signal line.

[mon2]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Also review this thread - your problem may be the same.

https://www.badcaps.net/forum/showthread.php?t=102720

[reformatt]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

https://repair.wiki/w/A1466_2015-201...9D_MacBook_Air

[reset1986]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Hi everyone!

I'm working on a Macbook Air A1466 EMC 3178 Board 820-00165-A that doesn't power on. No liquid damage. No fan. I've tried various power adapter, no green nor orange light.

PPBUS_G3H is 8.18V, and from what I've read on other threads it seems that SMC is not communicating to the ISL chip, but I don't know what to do next.

Thanks in advance for help or advices.

check that there are no shorts and check the voltage on the lines, smc_bc_acok,

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Hi, thank you for your help.
I'm using original adpters, and the contacts on the magsafe are clean.

Here are the voltages:
R7005 15V
R7006 8.18V
PPVIN_G3H_P3V42G3H 14.75V
L7095 3.42V

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Thank you for the link, it is very helpful

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Thank you for the advice.
I checked the voltages, there are no shorts, and smc_bc_acok seems fine.

[mon2]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Post the voltage of SYS_ONEWIRE.

[reformatt]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

If PPBUS_G3H is 8.2V then the SMC is not communicating with the ISL chip. Reasons for this are well covered in the RepairWiki link I posted earlier. The most common cause is SMC_RESET_L being stuck low and it's usually related to J6100 having crap on it. Clean it with a toothbrush and IPA even if it looks ok.

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

SYS_ONEWIRE is 3.399V

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

SMC_RESET_L fluctuates between 1.5V-0.4V
It might be SMC_RESET_L being low.

[mon2]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Have you cleaned J6100 with alcohol as per @reformatt's suggestion ?

[stellablu]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

SOLVED!!
It was R5100, changed it, now the laptop turns on and works fine . I'm so happy
Thank you all for the help.

[mon2]

Re: Macbook Air A1466 EMC 3178 Board 820-00165-A no power

Good job !