Macintosh SE Dead ADB Ports/IC

Does anyone have any experience with dead ADB ports on an SE? I stupidly plugged an S-Video cable that bridges pins 1 and 2 together and 3 and 4 together which I'm pretty sure killed the ADB ports on 2 SEs that I have.

I tested one of boards and it looks like the Tokin filter is still good which makes me afraid that I either fried the ADB chip or the VIA. I don't see any physical damage on the board.

I'm not sure how best to test ths ADB and VIA chip for damage, or if there are even replacements out there.

I came across an old thread about making modern replacements for the ADB chip, but it's a bit beyond me. I also saw there's an adapter board for ADB chips from later Macs.

Also, the computer boots up just fine, but no combinations of keyboards and mice will work.
 
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I checked out the transistor and was getting what I think are some bad readigns from it after compairing it to a good SE logic board.

  • Red probe to Base and Black probe to Emitter
    .6v - matches a known good board

  • Red probe to Base and Black probe to Collector
    .57v - matches a known good board

  • .7v and .688v for swapping each probe - matches a known good Board

  • Black on collector and red on emmiter is.163v while red on collector and black on emitter is 135 ohms (there was no voltage reading for this one). This does not matche my good board. On the known good transistor black on collector and red on emmiter is .32v while red on collector and black on emmiter is .27v

I'm going to order some transistors and see if that's the issue. Fingers crossed it's this easy.
 
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