Non working keyboard; bad caps to blame?

[Smith84]

Hello agian,

Here I have another mainboard. It is a FIC AZ11. My problem is when I turn it on, the keyboard doesn't work unless I pull the plug up, and push the ports forward. (see pic) I have tried several keyboards, but same result. The bios reports the keyboard as having an error, then I pull and push, the keyboard lights flash and the keyboard works... as long as I hold it there.

I read about another user replacing the caps, even though there was no apperent damage. After that the board worked correctly again.

This mainboard has CHOYO Capacitors, and is an AMD Athlon socket 462, currently at 650.

(what I have to do to get it working)
www.geocities.com/anothersmith84ftp/2.jpg

(suspected bad caps)
www.geocities.com/anothersmith84ftp/1.jpg

Hope I dont exceed the bandwith limit, pics are 2272x1074!

[willawake]

Re: Non working keyboard; bad caps to blame?

no need to host the pics offsite.

i have indicated two definitely bulging caps. the others look ready to go as well.





recommended to replace all choyo crap.

[kc8adu]

Re: Non working keyboard; bad caps to blame?

and a bad jack or broken solder joints if lucky.
unreparable if unlucky and it has a trace fault between layers.

[Smith84]

Re: Non working keyboard; bad caps to blame?

Do you think the badcaps are causing the keyboard error? I do bend the PCB a little when I push and pull, so could I be completing the circut of a bad cap?

I will take your advice, willawake and try to replace the caps. On the whole motherboard, I count 12 choyo caps. Only 2 look bad, the others look normal. How long do you think the caps have? I'd perfer not to recap them since the board is older.

Should I replace all the caps? There are 10 more TEAPO capacitors, smaller than those in the pic. Also one more Choyo, the smaller size. There are about 20 tiny caps too.

kc8adu, said if I was lucky... its only the jack or solder points. Do they sell replacement ports?

If im unlucky, im gonna trash it. Too much work for a 650 mhz.

[kc8adu]

Re: Non working keyboard; bad caps to blame?

i just heatgun them off of dead boards before i toss em.
take a real close look at the joints onder the kb/ps2 socket
look for ring cracks around the pins.

[yanz]

Re: Non working keyboard; bad caps to blame?

maybe you have a usb keyboard to live with... ( a temporary fix)