Dead USB Port(s)

[ChrisHA]

Hi;

My iMac 27" (mid 2011) has four USB ports, one of which initially appeared to be dead. I reset the PRAM to no avail. I then reset the SMC which brought the dead port back to life but a different port went dead. I rest the SMC two more times after which a different port goes dead.

This seems to have started after installing 10.11.3. Any thoughts?

Chris

 

[chscag]

Probably coincidental since the update to 10.11.3 had nothing to do with the USB ports or hardware. You said you reset the SMC on your iMac, how long did you leave it unplugged from the AC outlet? Try leaving it for an hour or so to let the machine cool down completely. If you still have problems after that, it might be time to let Apple run diagnostics on your iMac.

 

[ChrisHA]

Holy toledo! That seems to have done the trick. I pulled the plug, waited 2 hours, and continued the procedure.

Many thanks; Chris

 

[chscag]

Glad to hear it. The SMC reset for an iMac is sensitive to heat buildup which is why leaving it unplugged for an hour or so usually works better.