Electrical gremlins in my 92 SHO HELP!!!

[RedDemonSHO]

2 QUESTIONS to all i have a 92 SHO with 2 electrical problems #1 every time i turn on the turn signal on either direction the ETAC and stereo blink??? #2 the doors im my car randomly lock, like when i put it in to reverse, turn on the dome light, every once in a while when i shut the door. ITS NEVER DONE THIS BEFORE(never locked the door when i shut it unlike my 93 SHO) ive owned the car 6 years. its been doing it for like 2 months now. any help would be nice tried just about everything (cleaned switches, changing switches, testing wires, ETC) THANKS

 

[Eric VerValin]

I just had that lock thing show up on mine oddly enough. Normally it does it when I shift out of reverse and into first, but sometimes it lags... won't happen until I hit the bump at the end of the driveway. I'm leaning on a loose ground. I had my entire car apart, and everything was out and loose at one point.

With you saying it happens when you shut the door, makes me think its a ground on that side of the interior. There are a few around the pedals that come to mind.

 

[Racer X]

There's an unused connector under the driver's seat that's responsible for the locking when leaving reverse. It's either shorted, or you've accidentally plugged your seatbelt connector into this harness.

On the dimming when signalling (or in my case braking), either the dimmer switch is the culprit, or the MFS is.