My front doors courtesy lights do not work. The door switch, dome light, the door indicators in the dash, and everything works, but the little door lights dont. I replaced both bulbs with the same thing, too. I cant find the fuse that powers it, or anything about the circuit for the lights in the shop manual. Theres the dome light, the ashtray, cigarette lighter, key, and what-ever other lights you can think of, but not those. Any information would be helpful.
check the lil black thing on the side of the door if it slides out when you open the door if not it could be getting stuck or check the ground
The door switch, which i imagine is the little black thing your refering to on the B pillar, slides. The dome light and all other things hooked up to that switch work, too. Ill check the ground, and positive for the light, as soon as i can.
All the switches work, like i said, for every other component that use the door switches, aka the dome light and door ajar indicators in the cluster. I checked the ground, on a spot i thought would have a good connection. No ground. Im gona check straight to the batts ground asap. Maybe i should check out the wires in the door panel itself after that. Has anyone here had and looked into this type of problem?
check the connector behind the door panel, i had one come loose and the light didnt work, simply plugged it back in and presto
the switches don't actually control the lights directly, the lights are controlled by transistors in the safety indicator module in the dashboard, I found this out the hard way, while trying to trace a failed dome light. if you add lights that module can fail, sometimes it can fail and just knock out one set of lights, check all connections first, before you start tracing up to that
I was going to add, I traced out an entire circuit on a bad safety module, in the wiring diagram it will show diodes in line in the wiring, they are there, but they are all inside of that module, the wiring diagram simply shows the circuits, it doesn't actually show where the components are. there is a wire for each door switch, and trunk or hatch switch, they all go to the module, then there is a grounded switched wire out of the module for the dome and courtesy lamps. this is the same reason, if you unplug the instrument cluster, the dome light won't function.
Last edited by lostforawhile; 07-24-2010 at 07:20 PM.
The only thing about all this, is for some reason the courtesy lights in question arnt actually in the wiring diagram. Theres only the trunk light and the dome light in there. I'd have an easy time figureing out the problem if i knew what to look for. I guess ill pull off the door panels and start testing for ground and power. I hope it turns out someone went into the front doors for some reason or other and forgot to plug the lights back in, or something to that effect.
Hey, does anyone have a pic of the front courtesy lights in action? Ive never actually had a 3g with these lights working.
MY wiring diagrams are missing from my book now, but I believe the courtesy lights are tied into the ground for the dome light. they won't come on when you switch the dome light on manually, because you are switching in a different ground circuit, for that, but they should have a constant hot wire, and a wire going to the dome light ground circuit.Originally Posted by Ayeobe
Only one of the rear lights come on when one door is open.. where the dome light turns on no matter what ground is open, which makes sence. So, do you think its a part of the circuit somewhere, or its just not included, and wired the same way as the dome and trunk light?
something like this:
And i guess with the one-direction diode.
Agreed. They're often forgotten about when the door panels are removed and replaced.
88 LX-i coupe auto (241K DD), 88 LX-i coupe 5-speed, 89 SE-i coupe auto.
CARDONE SUCKS.
it's designed into the circuit that way, each door input has a diode, the ground for the light is probably past that diode. the diagram isn't whats actually in the warning indicator, it shows the dome light directly connected by diodes, in the one I dismantled and traced, the diodes switched on a transistor, which operated the light.Only one of the rear lights come on when one door is open.. where the dome light turns on no matter what ground is open, which makes sence. So, do you think its a part of the circuit somewhere, or its just not included, and wired the same way as the dome and trunk light?
something like this:
And i guess with the one-direction diode.
Damn, that sucks. I guess ill hope the connectors are unplugged. I can read a circuit diagram, but theres nothin useful on this one, so im kinda screwed.
Let me see if i get it so far. The ground switch for the door actually goes to the control module only. From that it turns on both the dome light and the light for the specific door using transistors? No wonder they didnt put it all in the diagram.
everything is routed to the module for simplicity, it has inputs for the doors and outputs for the lights, I wonder if some of them are different? like the 2 door vs 4 door? I know I have a four door sedan one in the hatch now, I couldn't find another two door. the second set of doors on the diagram don't do anything is all. I know the two door module had empty slots for the second set of door LEDS ,as well as empty slots for the auto transmission indicators. you could probably put a four door auto one in a two door manual hatch, the lights for the shift would be hidden by the missing holes on the gauge face. they wouldn't do anything, since the harness connectors wouldn't be there. if you ever have a module problem in the diodes, a simple multimeter and an assortment pack of diodes will fix that
When trying to draw the diagram including the courtesy lights i figured out why they'd need a module. If the dome light lights up at every single door, the wire for it goes to all the grounds.. Basically you need the module to seperate the grounds for the dome light and the 4 seperate grounds for the courtesy lights, or they'd ither all go on at once, or odd things would happen.
So i guess for these two tiny lights im gona bust my head more than an engine-cranks-but-does-not-start problem. Wow.
they could do the same thing with diodes in the car, but it's a much simpler solution to put them in one place, vs all over the car. plus the same diodes cause the proper LED to come on when the door is opened. if it was wired separately, you would need wires and diodes for each door, four wires going to diodes for the dome light, and even more diodes and wires to make the safety indicator work. this cuts way down on complexity
Theres a clue, then. All four of the lil red marks for the doors light up when the doors open. The signal gets to the module, but ither the 12v dosnt get to the lights, or the ground is gone. Im going to concentrate on problems that would cause both to stop working at once. Do you know if both lights are grounded at the same place? Or where ther 12v comes from? If its all on the dome light fuse, like the trunk light/dome light are together, then we can rule out the positive untill it gets into the doors or so.
I'm not even sure if all the courtesy lights come on at once, since i don't have any, I would assume the power comes from the dome light circuit, but they do strange things. you need to check for voltage at each light, the ground may well be switched by the same ground as the dome light.
I tested it just before, i opened the right rear door, nothing hapened at the left rear. They're seperate. I just dont know how. Good thing its simplified, huh? Shit, its just lights.
Im guessin the ground might be the same, but shit, i dont realy wana start takin stuff apart.. i guess im going to have to, just for a light. Ohwell, i wanted electrical troubleshooting, i guess this is as hardcore as it gets.
Ok this is how it's wired, strange but true, all the door switches are separated in the safety indicator by diodes and the dome light connects to all of them, each courtesy lamp goes directly to it's door switch, with the resistance of the bulb preventing feedback to other lamps, I don't see any diodes for them, all courtesy lamps are powered from the same power, as the dome light, and cigarette lighter. if the dome light doesn't work, it's the fuse under the hood, I can't remember which one it is, but I think it's 15 amps.
I kinda get the idea, but im more of a visual person. I see the diodes in the wiring diagram in the shop manual. Are you saying that the power for the courtesy basically goes through the light, then to the ground switch, and the reason they dont all light up is cause of the resistance in the bulb?
they all share the same power source, which is the same fuse as the dome light, and each one goes directly to ground through it's respective door switch, no diodes for those, the lamp in the circuit keeps current from feeding back and making all of them light up.
Alright, but it still goes through the controll unit? I hope its just a lose connector in the door, and nothing more. I guess ill start by pulling off the door panels in the 87 first.
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