My turn signals weren't working and I couldn't figure out why, I popped this off thinking it was my flasher/relay for em. Take it up to Advance and the guy had no idea what it was. Puzzled i went home plugged it back in and came inside to do some research. Turns out I was just missing the fuse for whatever reason. Plugged the fuse in and it worked fine. But I still have no idea what this is. Turn signals, wipers, lights, everything seems to work without it. It's off of a 1996 2.5l Cherokee btw.

 

Looks like the dome light delay.

 

Well, that would make sense, I just assumed the dome light was burned out but I'll look into that. Thanks!

 

Can you post a pick of where that relay plugs in? I am having issues with my interior lights, not shutting off, that I can't resolve. Didn't know there was a relay......

 

It is a delay. Has a bi-metal strip in it similar to a turn signal blinker. When the door is opened, it heats up the strip and turns on the dome light. When you close the door, it cuts power to the heating element and keeps the dome light on a few minutes. I have seen them go bad and stick in the on position. I built a replacement a long time ago for my dad's Ford Truck using a large capacitor, a resistor and a relay. Worked better than the bi-metal stock one.

 

It is. My dome light switch used to be broken, stuck on, so I had no bulb in it. One day I burned my leg on that thing, pulled it out, fixed the switch and put in a bulb.