Blown cap on A8N Deluxe

[davmax]

It looks like a blown cap at the end of the 1394 header. The mobo seems fine otherwise. I would like to find out the identity of the cap and if possible get some idea if any other component maybe damaged. So anyone with an A8N Deluxe may be able to help. I am reluctant to do RMA as it might take out the computer for some time. See pic

Currently there is about 12 volts on the right hand side and about 9.5 volts on left.

Thanks in advance.

[davmax]

Re: Blown cap on A8N Deluxe

I have now removed the component and cleaned up and surprise the component is labelled L27. This is hopeful in that it will mean no stress on other components have excessive voltage as with a coupling cap. A very small inductor!!!!

An input welcome.

[davmax]

Re: Blown cap on A8N Deluxe

Well I have managed to get back to this mobo and verified my suspicion that the inductor was a choke in the 12V supply to the 1394 header. So somebody shorted the 1394 supply externally. This now reassures me that the rest of the mobo is unharmed.

[davmax]

Re: Blown cap on A8V Deluxe

For closure I have installed a 470uH discrete bought from RS Components.

Picture not as clear but enough.

Board is A8V not A8N

[tazwegion]

Re: Blown cap on A8N Deluxe

Nice work davmax as always

[archae86]

Re: Blown cap on A8N Deluxe

Well I have managed to get back to this mobo and verified my suspicion that the inductor was a choke in the 12V supply to the 1394 header. So somebody shorted the 1394 supply externally.

I've heard that a lot of folks hot plug 1394 connections, and usually get away with it, but that there is a non-trivial severe damage rate. Not sure at all what the difference is between a "no problem" connection and one of the severe damage incidents.

Do you think it possible this board was a casualty of hot connect gone bad?

[davmax]

Re: Blown cap on A8N Deluxe

Do you think it possible this board was a casualty of hot connect gone bad?

Yes it is a high probability. Depends on mode of short. Will have to wait for a 1394 device to test operation.

[bgavin]

Re: Blown cap on A8N Deluxe

I have seen folks plug USB connectors upside down. That usually crowbars the PSU and everything goes to instant off. One client has done this several times with no damage (detected) to the board.