Apple MacBook Air A1466 (820-00165-A) no post

[koby058]

hi

Laptop does not power on, charger gives green light then turns orange.

Magsafe = Green to Orange LED
Magsafe with battery = Green only

Fan = Not Spinning

PPBUS_G3H = 8.58v
PP3V3_S5 = 3.343v
PP5V_S5 = 5.101v
PP3V3_SUS = 3.342v

Can you please help find the problem

[reformatt]

Re: Apple MacBook Air A1466 (820-00165-A) no post

Look for corrosion on the board, especially on the edges top and bottom. As you don't mention any other voltages, sounds like you are not getting to S4. First rule out you are getting a single (or double) pulse on all rails when power is first applied. If not, then review PM_SLP_S4 pre-requisites from logi.wiki.

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

thanks for answer

"First rule out you are getting a single (or double) pulse on all rails when power is first applied" can you please explain How i do that?

[reformatt]

Re: Apple MacBook Air A1466 (820-00165-A) no post

In this context, a pulse means the voltage for that rail appears momentarily and disappears after power is applied.

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

I have found some corrosion here in pic

measured resistance on R1915 R1916 0.99Mohm C1915 C1916 no short

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

any idea? any direction ?

[reformatt]

Re: Apple MacBook Air A1466 (820-00165-A) no post

https://logi.wiki/index.php/G3_to_S3..._and_Broadwell

[rediii]

Re: Apple MacBook Air A1466 (820-00165-A) no post

search for broken traces on contact points too, these boards do have delicate problems with it…

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

Thanks this was a great idea

found out in the corrosion area that PM_RSMRST_L is low

while on U8130 pin1 PP3V3_S5 is high 3.3

resistance on R8133 is 38K should be 100k.

what do you think is the next step ?

[reformatt]

Re: Apple MacBook Air A1466 (820-00165-A) no post

Remove the IC and check all connections to it. PLT_RESET_L should be pulled high by R8133, and only pulled low by U8130. This is either after a preset delay, or when PP3V3_SUS is missing on pin 2. Also check resistance of pin 6 to ground.

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

Hi

Since i can only remove the chip in the morning, i have measured what you have asked today. but then i have measured also pin 3 of U8130 and the minute i have touched it with the probe the fan start spinning and i see the mac boots.

also i have found out that C8131 is totally missing from the board.

but it is present in the board view.

Is it better if i just install a new 1000pf cap ?

[reformatt]

Re: Apple MacBook Air A1466 (820-00165-A) no post

C8131 is NO STUFF and not fitted.

[koby058]

Re: Apple MacBook Air A1466 (820-00165-A) no post

OK, so for today i have found out that PP3V3_SUS is present on pin 2

and 330Kohm on pin 6, tomorrow i will remove the chip and test again