[SOLVED]820-2936 headphone socket issue

[brrayne]

Hi there,

I have an 820-2936 and I'm trying to diagnose an issue with the headphone socket. When I got this board, the computer wouldn't switch to the headphones when I plugged them in. After inspecting the board I noticed there were a few components that had been knocked off around the headphone socket: R6881, R6882 and C6885.

I replaced them, but the issue remained. I have found that if I have the headphones plugged in when I start the computer, they work fine, then if I unplug them while the computer is still on, it automatically switches back to the speakers, but if I plug the headphones back in again, the computer doesn't recognise them.

I would appreciate any suggestions.

Thanks in advance,
Bruce

 

[dukefawks]

R6700,2, R6801,2,3,4,6 all present and correct? Voltage on Q6800 pin 2 and 5 and Q6801 pin 5 with and without headphone plugged in. No need to boot OSX for these tests.

 

[brrayne]

Thanks for the quick reply.

All of those resistors are present and correct. The voltages on Q6800 and Q6801 are as follows:

No headphones:
Q6800 pin 2: 3.2V
Q6800 pin 5: 0V
Q6801 pin 5: 0V

With headphones:
Q6800 pin 2: 0V
Q6800 pin 5: 3.2V
Q6801 pin 5: 3.2V

I think this part's working the way it should, yes?

Thanks again.

 

[dukefawks]

Yeah that's fine. What is AUD_IP_PERIPHERAL_DET with and without headphone?

 

[brrayne]

AUD_IP_PERIPHERAL_DET is 0V without headphones an 3.2V with headphones.

 

[dukefawks]

Also correct. Now it is gonna get annoying... what is a AUD_SENSE_A voltage with and without HP? Did you thoroughly check for any more damaged/missing components around HP jack and U6201?

 

[brrayne]

I ended up replacing the audio port, and the problem is now solved. I think that while I was testing with the board in the case, it was creating some intermittent contact issues, resulting in the problems I was having. While I was testing with the board out, everything worked fine (hence all the positive results).

Oce again Duke, thanks so much for your time. You can mark this one as "solved".

Bruce