Accessory Relay issue????
 

Just replaced the head unit after finally getting a factory harness and retro universal harness. Issue now is, door locks and dome light will not operate unless car is running. Is this possibly the accessory relay blown due to possible short during installation?? Thank you.

Check the "back up" fuse under the hood. It supplies power to a bunch of stuff when the key is off.

I agree with mr. mk378, but I would like to add; if a relay is inoperative (doesn't energize) then it wouldn't work intermittently as you described (in most cases). I made a video on fuses and relays a while back; you may find this to help you understand relays a little bit better. Here's the link to that YouTube video The ALE-2 Fuses and Relays: How they work - YouTube

Also if it's a 2001 - 2005 there is a "multiplex control unit" built into the under dash fuse box. It controls a lot of things like the locks, intermittent wipers, dome light, and A/C compressor. They are prone to fail for basically no reason.

Thank you to all. This is a fantastic site, with many very knowledgable people. Turned out to be the back up fuse. Thanks again.