While testing a class A amplifier circuit I built, I accidentally connected +12V to the audio output of the headphone jack, and now no audio works, but otherwise, the computer works just fine. I want to know what is broken so that I can replace it. Nothing plays through the speakers, but using pavu control (fedora 36) it still thinks it is outputting, so I think the speaker circuitry may be damaged somehow.
So when you say no audio works, you are talking about audio through the headphone jack and audio from the build in speakers i guess?
Hard to say how far you sent the 12V…
I would start by disconnecting the audio board and check, if that brings back the sound from the internal speakers.
Check if you see any burnt components or discolorations on the audio board or in the area the audio board connects to. Maybe provide some high res pictures.
Check the underside in that area as well, if you feel comfortable removing the board from the case.
If you have a multimeter at hand, check the capacitors on these areas for shorts.
I guess you could have fried the audio IC though, which would require a whole new motherboard, unless you have experience with microsoldering and can get your hands on a replacement IC…
the audio does not work for the speakers either, and I am pretty confident with repairs, but not with microsoldering. Part of the plastic sheet glued onto the motherboard has a raised bump, and underneath it is a microchip that smells like burnt electronic, so I don’t think that’s good at all, and I may just need a new motherboard. Than you for the help.
Might not be worth the purchase, perhaps look into a USB-C DAC?
If the chip is not totally burned, you could try to confirm if that is the audio IC.
Its either a realtek ALC295 (ealier units, around 10€, according to google) or a Tempo 92HD95B (cant find a seller right now).
Depending on where you live, you may have a repair shop around, that does component level repairs or maybe someone from the community, who is capable and willing to help out
This is definitely hardware damage. Please open a support ticket and let them know the steps you took to arrive at this point. They will be able to help.