So I have a 99 Chevy Suburban, K1500 4WD, (old body style) w/o overhead consoleand recently have had the following problems with the interior lights:

1. The dome lights (front or rear) never come on when the any of the doors open, the courtesy lights under the dash and the doors do come on.

2. The reading lights up front work sometimes, but not very bright. (Not as bright as they used to be).

3. When I close the doors the courtesy light stay on for about 30-45 seconds, then they dim. But they never turn off completely.

I've replaced the door switches, and the headlight switch to no avail. (I also made sure that the Dome light override switch was off, but it makes no diiference either way).

I think all these problems are inter-related, but I'm kind of at a loss. I've heard some people say that it could be the RMK (Remote Keyless Entry) Module, the Interior Lighting Module, and I've even heard that the RMK and the ILM are actually one unit or module. Could someone please clarify?
Also can someone show me a picture of what I'm looking for?
I could also use a wiring diagram if someone has one?

Any help would be greatly appreciated.

 

Welcome to the forum.

First thing I'd check is the circuit grounding.

 

try checking the interior lamp control module located under the center of the IP, this is from the 97 manual but I suspect they are in the same locations....

 

Got a new lampcontrol module on order, should be here Tuesday. I'll post results, Hopefully this will help someone in the future.

Thanks for the input.

 

I've got the same problem with my 98 Suburban. Did the lampcontrol module swap fix it?

Thanks

 

OK-I've had the fuse (#3) out for a few days. I put it back in and the dome light was off. I opened the door, and the dome light came on. I shut the door and the dome light went off after 45 seconds. Sounds good eh?
Then I open the rear door, light goes on. I close the rear door, I hear the relay click after 45 seconds but the dome light stays on!!!
Every time I open a door and then close them, after 45 seconds I hear a soft click under the dash which I assume is the delay relay. This would rule out the door switches being the culprits since they are good enough to trigger the delay relay timer.
There must be a module under there that's confused or shot!

 

Sounds like a bad relay.

 

Is the relay located on firewall near the parking brake (old fusebox location)? I don't have a wiring diagram.

Thanks.

 

The lamp control module is under the dash near the brake pedal

 

Sucess!!!!
After checking all switches, relays and combinations of fuse in and fuse out, the problem was a short in the wiring harness way up behind the dash. The GM tech thought it would be an Interior Lamp Control Module but after cuts and bruises, I had my hand way into the belly of the beast and found the lights would go out if I moved the harness around.
I still haven't completely fixed it since it's way up in the back of the dash so I've just got it wedged away from where it was. I guess I'll have to take the gauge cluster out so that I can see what's going on.
Thanks for all the replies.