MP 1,1-5,1 MP5,1 rear USB ports no longer working

[Cave Man]

Hmm, seems a complete shut down and unplugging the AC for 10 seconds solved the problem.

This is weird. I used my MP5,1 two days ago and all was fine. Woke it from sleep just now and my keyboard was not responding. I unplugged it from the rear port and tried another rear port but no luck. Connected it to the front port and it worked just fine. So, restarted the MP with the keyboard in the rear port but it does not work. I have to plug into the front ports. Any idea what my be going on? Mojave is the OS.

 

[haralds]

That's likely an SMC reset. The full routine should be:
- Shut down
- Unplug
- Wait 30s
- Plug in
- Wait 5s
- Boot

 

[Cave Man]

That's likely an SMC reset. The full routine should be:
- Shut down
- Unplug
- Wait 30s
- Plug in
- Wait 5s
- Boot

Hmm, did it again but this time no luck after shutdown. I did this list twice but it doesn't fix it. I will try the keyboard PRAM reset next. This all started when I connected the keyboard to a USB port on my 27" ACD that is plugged into a port on the back of the Mac Pro.

I also connected the ACD USB cable to a front port (using a USB extension cable) but the ACD ports still don't seem to work.

Edit: Well, after dinking around with it for 30 minutes, unplugging, waiting, resetting the PRAM, resetting the SMC (Option-Shift-Ctrl) I have the keyboard working on a rear port. Not sure if it's solved (probably not) but I'll just see how it goes.

 

[Cave Man]

OK, so it turns out I can only reset the PRAM with the keyboard plugged into the front USB ports (Option-Ctrl-P-R). The keyboard isn't even recognized if plugged into the back ports. (Apple aluminum extended keyboard.) The first time I reset the PRAM, the keyboard worked when plugged into the back. But then I plugged it into the ACD to see if that was fixed, too - but it wasn't. Plugging the keyboard back into the rear port was not function. So, I rebooted again resetting the PRAM (4 chimes in total) but now the rear ports do not work for my keyboard. This is really a strange problem.