A1466 MBA weird shutdown issue

tlough75

Member
So I have a really strange issue I have not encountered. I replaced a keyboard and track pad on a MacBook Air due to liquid damage and the machine starts up fine, the fan does not run at high RPM, when I run the Apple diagnostic test it doesn't report any sensor issues however the only way I can shut the computer down is by holding the power button with either the battery connected or the charger, but not both. when i attempt to shut it off with both it will simply "restart". If I shut down using OS it is the same deal, will only restart. has anyone ever experienced this before? I tried to use a different keyboard and same deal. Will only stay shutdown with power button held. I'm hoping we can solve this so others may learn.
 

2informaticos

Administrator
Staff member
First of all, disconnect TP flex and see if you can turn off the board with R5115/16 pads, instead of power button.
Post 820-XXXX (always required) if you really need help.
 

tlough75

Member
Ok, tried the power on pads and get the same result. Board will act like it is off for 1.5 seconds then turns back on
 

2informaticos

Administrator
Staff member
What is the exact voltage for SMC_ONOFF_L signal?

Also post voltage for ALL (4) PCH's RTC signals.
Take you time and use search function on the forum, if you don't know which them are.
 
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tlough75

Member
RTC_RESET_L: 3.32v

PCH_SRTRST_L: 3.32v

PCH_INTRUDER_L: 3.08v

PCH_INTVRMEN: 3.23v

SMC_ONOFF_L: 3.45V
 
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tlough75

Member
Decided to measure the resistance of the resistors for these signals and R1302 for PCH_INTVRMEN is reading 18k ohms vs the 330k it should be.
 

2informaticos

Administrator
Staff member
Is the battery correctly recognized and charging?
Try known good battery; even old, just for test.
Also try known good LIO board/flex.
 

tlough75

Member
Ok so I re-ran all of the power down tests again to make sure and it looks like any time the charger is plugged in it will not shut down normally. With only the battery plugged in it will shut down and stay off if I use either the power button on the keyboard or shut it down using MacOS. If I have the charger plugged in while shutting down the current will dip from .7 amps to .2 before starting up again with or without the battery plugged in. Seems to me like a charging circuit issue, although the battery is able to be charged.
 

2informaticos

Administrator
Staff member
If charger is connected, doesn't stay off pressing power button 4-5 seconds?
Same issue if SSD is disconnected?
 

tlough75

Member
If I hold the power button the current drops to 400 milliamps and the computer will restart, with or without SSD
 

tlough75

Member
I'm going to try to hold it for like 10 seconds but I'm sure it will just sit and wait for me to release then restart
 

tlough75

Member
ok, going to try that next. I held the power button down for 10 seconds then unplugged the speakers so it wouldn't wake up my kids restarting it a bunch of times and now it will stay off, but now when i plug in the charger the charger will not turn the computer on. Isn't the charger supposed to start the computer on a 820-3437? Will post back with results from removing airport card...
 

tlough75

Member
ok, now it starts normally when charger is plugged in but will not stay off when told to via MacOS. Oh and removing the Airport card seemed to do nothing...
 

tlough75

Member
I just checked my receipt for the Trackpad, and it is for a 2013-2017 Air. This is a 2014. Could it be the trackpad? I mean the trackpad responds well to cursor movements. I'm at a loss here...
 
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2informaticos

Administrator
Staff member
Power button is not processed in the trackpad circuitry.
And I think you got same issue w/o trackapd, using directly R5115/16 pads.

If now issue appears only from OSX, try new installation in other SSD; or USB test OSX, disconecting internal SSD.
 
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