I have a '92 lt1 automatic coupe and am having a problem. It has been occuring of and on for awhile now. For some reason the interior lights will not go off. The only way I can make them go off is to take out the fuse that controls them. (I think it is the top left fuse in the fuse box, but not 100% on that) Of course my first guess was that the car still thought one of the doors was open, but the signal on the dash showing a door is open isn't lit up. I've checked the switches on the door that show the computer the door is closed, and they appear to be fine. My other thought was that it would maybe be the switch on the dash that turns the lights on, but it still has a very positive click when you turn it up to turn the interior lights on, and although I guess it could possible be something to do with that switch, I wouldn't understand why it would work perfect most of the time, and mess up just every great once-in-awhile. When it happens after I take the fuse out I can usually let the car sit for a day or two and put the fuse back in and it will work fine for another week or two before it happens again. I've talked to a couple people about it and they think it could possibly be a computer problem. (not the main computer, and I can't remember the acronym for this one, but in fords it's called a bcm) I really don't want to replace that and then it turn out that's not what it was, and I'm just wondering if any of you have experienced this before, and if so, how you fixed it. I really don't want to have to start tracking down wires everywhere to look for a short, and I'm hoping it's something a little bit easier to fix.

Thanks in advance for your help!

 

you mentioned the door switches, but have you checked the rear hatch switch? I went through three before I discovered that my hatch vent was damaging them.

Right now
I have the hatch switch unplugged(you can access it by removing the rear trim panel). Haven't had a problem since.

 

No I haven't checked the hatch switch yet, but on my car when the hatch is open only the lights on the pillars light up, not the lights on the front doors. When this problem happens, every single light in the car lights up, so I wouldn't think that it would be the rear latch, but I might try that just to eliminate it as a possibility.

I've searched the forum in the last few minutes and have seen where several people have had a similar problem caused by a timer module, but I think all of the people who said that had a pre-90 model interior, and I'm wondering if my 92 would also have this timer.

Thanks for the help!

 

Same here, mine was screwed up by a hatch vent and after fiddling with it I decided I didn't need the lights to come on when I opened the hatch, which I rarely do anyway, so I unplugged it. To me, it wasn't worth the price of a new switch to have that function.

 

Do the lights go out after 15 minutes? If so, check to make sure the door lock cylinder switches work and are pointed vertically.

 

I'll check when I get home tonight about the 15 minute thing. I know that when I turn the key to unlock the door, the light comes on inside the car, and I do know that when I put my key in the door and when I take it out it is always vertical. Also, I have had this problem several times without the doors having been locked and without touching the door lock cylinders.

 

C4s&Sooners,

In my 85 I had this problem. I would get out of the car lock and close the doors and the courtesy lamps would stay on indefinitely. They also stayed on after starting the car. I replaced the courtesy lamp timer delay module and that fixed the problem. On my 85 the timer delay module is located behind the dash on the passenger side. I can not say of the system is set up the same on an 85 and a 92. If you have, or can get access to, a Chevrolet service manual for your car it should be helpful in figuring this out. The service manual for my 85 has a good electrical section that was a big help for me in figuring out what was going on.

Brian

 

I do have a service manual in the bookcase at home. I will look in it tonight and try to locate where the timer is located. Also, where did you buy the part and how much does one cost?

Thanks to everybody that's been trying to help!

 

I don't know the year that the terminology and wiring changed, but later C4's have a 'Delayed Accessory Buss' or 'DAB'.
Check your service manual for this terminology as well as 'timer'.
You might find a lot about delayed accessory buss on the 'search' tab above too.
Hope this helps, please post when you find the solution,
former Stroud resident.

 

the "DAB" is disengaged once you open the door.

 

Hey! I have this same exact problem. I have a 95 and I have the fuse out as well. All my damn lights won't turn off when the fuse is in, it's like they are constantly on. The only way I was able to figure this out is with the fuse. I havent taken it anywhere scared of all the labor it would probably take just to track it down.

Have you had any luck fixing it? I would LOVE to know so I can get a jump on actually fixing this problem!!!

 

anybody?