My interior courtesy lights are on all the time on my 86. I have new door jamb switches so I know that isnt the problem. I pulled the courtesy light delay box and even with it completely unplugged the interior lights still stay on. Doesnt the ground go through this box? With it unplugged shouldnt they go out or does it somehow work differently?
Anybody got any advice on where to look next?
Thanks
Roy

 

Rig the door switch on the passenger side to always be closed then pull fuses one at a time until they go out. Start trouble-shooting that circuit.

 

Thanks for the tip but I am way past that one. The fuse to that circuit has been removed for a long time because of this problem. I know which circuit it is, I just cant find the problem. According to my ohm meter both of the door jamb switches, and the hatch switch work. Both door ajar switches are new. The console switch is completely unhooked. I tried bypassing the delay box according to the archives but no luck there either. I am thinking it may be the dashlight switch at this point.
Roy

 

I had EXECTLY the same problems that you are experiencing. I replaced the door ajar switches, the hatch/convertible top hatch switches and all the fuses; all to no avail. I even removed what I thought was the courtesy light delay module and sent it off for repair. The shop replorted back that the module was working fine !

Long story short, what I actually removed was the low coolant relay which is just where many manuals say the courtesy delay module is located. TRUST ME, it is not there.

Here are some pretty good instructions on just where to find the courtesy light delay module and where it is actually located.

Call me if you need further help; I can helpyou with this MONSTER.

 

Thanks for that info. According to what you have posted I believe I have the right timer. I also have now pulled the main dashboard light switch to no avail.
So if I understand the wiring diagram correctly the ground to the lights is supplied thru the timer. This means that when I unplug the timer the lights should go off. Since they dont they must be getting a ground somewhere else. Does this seem correct? I must admit to electrics not being my strong suit.
Any suggestions where to look? Im stumped.
Roy

 

NO! It does not sound right. I think that you have pulled the wrong relay. The low coolant relay is under the passenger side hush panel up near the right side cooling duct. It is taped to the wiring harness with white masking tape. It looks like it is the courtesay light delay module, but it is not.

The courtesy light delay module is way up under the ECM module taped to a large 1.5" - 2" wiring harness. It is taped to the harness with manila colored masking tape. You can just barely see it if you remove the ECM mnodule first. When you locate it, you can just barely reach it with your hand. When you do, latch onto it and pull it off. Then you can pull it down far enough to unplug it. Be careful not to disrupt the other modules and wires that are mostly in your way.

Here is a photo of the courtesy light delay module (white) and the low coolant module (black) for comparison.

PLEASE NOTE, IF YOU THINK YOU HAVE THE RIGHT MODULE OUT AND THE COURTESY LIGHTS ARE STILL ON - YOU DO NOT HAVE THE CORRECT MODULE. I know; I have been there.

 

I dunno, Im going to go look again but...The module I have pulled out appears to have all of the correct colored wires. I pulled it out thru the front after removing my breadbox replacement panel. It was taped above a big wiring harness. I have the hush panel, the breadbox replacement panel, and the dash top removed at this point. I cannot see any other modules.
I believe the module circuit is working correctly. I notice if I close all of the doors, then after a short while the lights will dim slightly. If I reopen a door they will brighten back up. This leads me to believe I have a wire somewhere that is grounding out and turning on the lights. The module is supplying additional ground when it turns on/off causing the dimming.
But like I said, I will take another look.
Roy

 

If you have the module out, disconnected AND in your hand and the courtesy lights are STILL on - YOU HAVE THE WRONG MODULE. The courtesy lights can not work with the module out unless someone, somewhere has rewired the system to work without the module, which, frankly, seems remote.

 

Well you are going to have to rethink that theory.
There is definitely no other module. The only thing above where I pulled this one from is the air duct. It was between the air duct and the harness, on the passenger compartment side next to the ECM. It was in the exact location it was supposed to be according to your information. It looks right and it has all the right colors. In addition I get a ground on the twin yellow wires that go to it when I open the doors. I get power to the connector when I replace the fuse and lose power when I pull it.
Its in my hand, and unless I pull the fuse the lights stay on.
Power has got to be bleeding over to the lighting system from somewhere else in the circuit.
This following part seems to be wrong as long as I am reading the wiring diagram right. With the module unplugged I do not have 12v at the pink/black wire. According to your info this wire should be hot all the time. However I do have 12v at the orange wire as soon as I plug in the fuse. Again, if I read the diagram correctly this wire should be carrying juice from the module to the lights, it should not have power all the time. Am I correct about this? If so it explains why my lights are staying on, although not where the power is coming from.
Or if this wire is supposed to be hot all the time, and the module grounds the circuit, then I have a ground somewhere that is keeping them on.
Thanks
Roy

 

I replied to a similar post a long time ago. Idid some research on the wiring schematic and found an interesting circuit wiring path. I do recall that there is an issue with the ground somewhere that flows through a switch in an unrelated circuit. I'll try to find my post, maybe it'll help.

Art

 

There could be other sources for the circuit to be grounded. One could be in the RH or LH door handle light switches. I've seen these switches melt over time which could be causing a ground to your interior lights. Do they operate properly. You can test them by pushing on the end of the white lens to turn it on with the doors closed. You can try to remove the door bezels and inspect the back of the white lens since that is where the switch is located. Another obvious source is the headlight switch. Rotating it turns on the interior lights. You probably have already eliminated this switch but it is a source of ground.

Art

 

John:

Do you have a photo of the relay that you removed? What is the part # printed on the relay?

 

Art, You are the man. thank you, thank you, thank you.
Roy