C486Bill

Long story short, car has sat maybe two yrs before i decided to give it some long deserved love and get her going again. The interior lights, none of them come on when i open the doors, if I pop the rear hatch, the halo lights come on. Where should i start looking othr than the obvious meaning the bulbs under the dash. Also doesnt work if rotate the headlight switch
thanks for any help in advance.
Bill

crowz

You didn't list the year of your car but if its like my 87 try this.

Turn the headlight **** to the left and see if the interior lights come on. If they do but wont come on when the doors are opened the courtesy timer module has gone bad. Not fun to change. I'll wait and see if you post back with that being the problem.

C486Bill

Sry, It is a 86 and no they dont come on when the **** is turned. if both doors work if you press them as does the map light on the rear view.. Also, the two in the halo? work when you pop the hatch

crowz

Sounds like a blown fuse. Anything else not work?

Id just check all the fuses for the heck of it to be on the safe side.

C486Bill

Ill recheck them tommorow, hopefully something easy as that.

enventr

Could be the relay( same as fuel pump relay and I believe the horn) you can disconnect the horn or fuel pump relay to test it and make sure. Ecklers sells relays for about $16

C486Bill

Dont want to sound stupid, but where exactly is this relay and what is it labeled, or refered to as?

crowz

I have no clue what he's talking about relay wise.

enventr

Not a stupid question.Im just learning about this as I had a problem on my 95. The 90 to 96 the timer was moved into the CCM. Your year from what I read on the forum states the interior light delay relay is taped onto the wiring harness that goes to the fuse block and is located very close to the fuse block. Cliff Harris (forum member) is well versed on this. You may want to send him a PM. Good luck

crowz

Not picking at you. I just had no idea what relay you were talking about.

Unlike other cars people like our c4's are tricky.

I know probably 90% everything on a 1984 to 1990 (not even sure when they redid the interior for sure so may be 91) location, etc.

But that's from my 86 coupe I had and being around when people were still trying to figure it all out back in the day. Plus its been over 10 years since I raised the hood on a c4 till now so Im a tad rusty but getting back there

With these cars having the big change over to the lt1 motor and then the lt4, interior redesign etc it makes diagnosing what people put in the forum tricky.

I never feel 100% confident unless the op says 88 or older right off the bat for their car year and then I still try to double check anything I put in the forum. Probably will still make mistakes helping folks from time to time because of the changes across the years.

So again didn't mean that like "your wrong" as much as covering my butt with "I don't know what relay your talking about" since who knows maybe I missed something

But on this one his interior lights only have the courtesy module and fuses that effect the behavior of his interior lights other than the door switches and the headlight ****.

enventr

It's probably the courtesy module. Cliff Harris I believe has your year vehicle and that is where I got the info on the pre 90's vette . I hope he will maybe chime in and explain things better because he is very knowledgeable . He told me the location of your year plus mine which helped me out.

crowz

The courtesy module or the headlight **** can turn the lights on.

The door switches go to the courtesy module not the not the lights directly.

So if the **** on the headlights turns the interior lights on but the door switches don't the modules bad.

If the **** on the headlights doesn't turn on the interiors AND the door switches wont either then its a problem on the positive side of the circuit not the ground side.

The door switches and the headlight **** provide ground only.

So Im betting blown fuse or wiring issue not the module.