My radio, wipers and clock fail intermittently. It happens infrequently and usually on a longer trip. If I turn off the ignition and restart the engine everything is normal. My mechanic can't diagnose it unless it has failed. He has suggested a wiring short or connection, ignition switch, relay or engine control module. Thanks for any suggestions in how to diagnose or fix this problem.

 

Try swapping out the ignition switch not the mechanical part the electrical side with the plug.

 

It could be the ignition switch as The Fixer said. there are many contacts inside the ignition switch, any one of which could be getting worn.

When this happens, see if your side mirrors still work. They would also be affected by the ignition switch.

Also, just to make sure, what year is your car? The electrical systems vary a little from year to year.

 

I replaced the ignition switch. Will monitor to see if this is the fix.