When I insert my key about half way and move it ever so slightly, the interior light overhead comes on and fades out, just like it does when I first get in the car and shut the door. I know there are 3 sets of wires on a harness going to the key tumbler mechanism. The first set of wires (nearest the key insertion point) maybe is the problem? What is the function and how can I test this? Why would this be kicking on my interior lights when I halfway insert my key and move it slightly? Thanks.

 

is your key switch really loose?

 

If you mean a lot of play once it is inserted in, then yes, I guess so. Why? I thought it might be the ignition switch, and when I went to clean the contacts thinking it might be shorting it fell apart. I bought a new one from the dealer and put it in myself. The ignition switch itself is brand new and went in without a hitch. I was wrong in my assessment of the interior light problem I guess. I am still trying to figure it out.

 

The diagram below shows the circuitry connecting the BLK/WHT wire from the ignition switch to the Integrated Control Unit (controls the dome light).

 

Seems like every electrical problem I have right now lead to that black box, the integrated control unit.

 

Yeah, you probably should focus your electrical troubleshooting on the ICU.