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Interior lights

For the past couple of weeks, I have noticed that the inside lights are on while I am driving the car. When I try to turn them off, they stay on. Once the ignition is turned off, the lights remain on causing me to worry about running the battery down. However, after a while (not sure how long) they do go off. What is going on and how do I turn off these lights while I am driving?

If you’re sure the dimmer switch hasn’t been turned all the way up, which will turn on the overhead lights, then the problem is probably in a door switch.

I once had this problem with a Ranger. The overhead light would stay on no matter what. One day I watched, and after what seemed like a very long time the light went off, only to come on and stay on next time I opened the door.

Never figured out what was wrong. I took to removing the bulb so I could drive at night. One day I put the bulb back in and everything worked normally. I have no idea why it malfunctioned or why it went back to working normally.

My guess is that a switch in either one of the doors or the liftgate is sticking. These switches complete the circuit to the chassis of the car (ground). I think your car has a feature that will shut off the power to the lights if the battery voltage drops to a certain point. However, this isn’t the greatest thing to do for a battery and the alternator has to do more work to put the energy back in the battery. You do need to have this fixed.

In your case, I would bet that the overhead light in your Ranger was making contact with the chassis and completing the circuit. When you removed the bulb, you may have moved the overhead light fixture just enough to keep the socket from making contact with the ground.

The problem might be with the GEM (Generic Electronic Module). This contains the central timer for all the courtesy lights. How this is supposed to work is, when the doors are opened the interior lights come on. As soon as the ignition switch turns to the start position the interior lights should turn off. When the vehicle is turned off, and the doors are opened the lights come on. When the doors are closed, the central timer keeps the interior lights on for thirty seconds and then shuts them off. It would appear central timer of the GEM is malfunctioning.

The GEM is located behind the center of the dash.

Tester

Thanks. You’re right. I had no idea it was the dimmer switch. I feel so stupid, but so thankful that you saved me a trip to the mechanic for a big bill and further embarrassment!