Please help me

When driving my car with the A/C on all of a sudden the A/C starts blowing hot air, all the dash board guages stop working and the door locks stop working. The car is still running. If I stop and put it in park I can no longer get out of park. I disengaged the battery for 30 seconds and it all works again. My service engine light goes out as I reset it. This has happened to me twice. Also the fans stop working in the engine.

The ignition switch may be failing. With the engine running jiggle the key toward the off position and back repeatedly to see if you can cause the problem.

In an effort to “get to the bottom of this” what made you try disconnecting the battery cable?

You might “go smaller” and see if you can isolate this to simply pulling the fuse to a module.

Thanks for replying. My son-in-law thought to disconnect the battery because we couldnt get it out of park. Thats when we realized that everything started working again, hmmmm…we have tested all the fuses…

The trouble could very well be with a bad switch section in the ignition switch like Rod Knox stated. The trouble could also be due to a bad power connection in the power panel under the hood or the wiring to it. SInce you say the cooling fans are effected I am leaning towards the problem being under the hood.

Have your alternator checked for a bad or weak diode. This can allow an A/C ripple in your electrical system and computers DO NOT LIKE THAT and can react with symptoms like you described…

The PARK issue was not seeing the brake pedal switch functioning to trigger the interlock (stops kids in car seats from shifting the running car into DRIVE). That’s not part of the ignition switch.

It’s more fundamental …way further up the chain.