I have a IIc that is perfectly functional except for the space key. I've done everything I can think of to troubleshoot but I can't figure out what's wrong.
- Confirmed continuity on the switch when pressed & no continuity when released
- Confirmed continuity from one leg of the switch all the way back to pin 25 on the encoder IC
- Tested a different IIc keyboard with the mainboard to confirm the encoder works fine (it does - space key works fine with the known good keyboard)
- Confirmed the problem persists if I move the bad keyboard to another IIc (same issue with the space key follows the keyboard)
- Sprayed in the key switch with some Deoxit (also sprayed the cable connector)
I don't really know what to do next. This is one of the non-ALPS keyboards (they crappy ones).
- Ben
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You said you traced one side of the switch back to pin 25 of the encoder. Did you also trace the other side of the switch back to pin 34?
I forgot to follow-up on this thread with the solution. Not until *AFTER* I had gone through & re-flowed ALL the solder joints on the back of the keyboard I was able to find that one of the legs on the Return key was broken on the top-side of the board. I desoldered that switch & fixed the leg with a piece of 22ga wire. Now everything works perfectly!
Thanks for all the suggestions!
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