Logic Board (bare) won't power on - final checks?
I've got an A1297 which won't power on. I've tried a bunch of the usual troubleshooting steps, and have ended up failing to get even the bare logic board to power up.
The Magsafe light shines green, and I can see 19.3V and 16.5V at the logic board dc inlet (grey pair to black pair, and black single to black pair respectively). I can also see 3.3V across the power switch pads.
I've tried the "no battery boot" procedure (unplug everything, short the power pads for 10-30sec, plug in Magsafe, continue to short for 10 sec, open the power pad circuit, then close it again briefly to boot).
I tried a gentle reflow in my kitchen oven (10 min at 200°C), and that hasn't changed anything.
Are there any other diagnostic steps etc. I could take to determine what might have failed? The machine just stopped working one day - no liquid ingress or shock.
Thanks in advance!
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7 Comments
I also have a bare logic board that will not power up with the charger. I only have a fan plugged in and it does not spin. It does, however, boot if I connect the battery AND charger. Do we expect that it should automatically boot up when the charger is connected? I’m trying to figure out if this is a symptom of my main problem or normal behavior.
by lzrBeamer
@moley check your board. What is the 820-XXXX number on it.
by oldturkey03
@lzrBeamer is this for the same computer as questioned by the OP? What are you checking for on your board?
by oldturkey03
@oldturkey03 A different board (mid 2012, 15” retina) but my question is more general about booting up without a battery since OP discussed “no battery boot” procedure. Should the board boot and give fan spin by simply plugging in the charger?
by lzrBeamer
@lzrBeamer it is supposed to come on when you connect the charger. However, you most likely also have power on pads on your board.
by oldturkey03
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