How to debug “door open” light? (1 Viewer)

[t00manyuserz]

I’ve been trying to figure out why my door light stays open. I took apart the front switches and cleaned them but that doesn’t seem to have helped. Weirdly, when I press the FRONT switches, the light on the dash kind of briefly dims, whereas the rear switches have no effect, not sure if this is related or not.

How can I trace this? Is there anything I can short to remove the switches from the system entirely and start adding them in one by one to see which one is faulty? (and hope it’s not wiring shorting somewhere in the body…)

 

[gummycarbs]

remove the switches from the system entirely and start adding them in one by one to see which one is faulty?

Do that first.

 

[t00manyuserz]

Do that first.

If I do that though, will it deactivate the light? I haven’t tried yet. If so then yes that’ll be super.

 

[gummycarbs]

If I do that though, will it deactivate the light?

If one or more of the switches is a problem, yes.

 

[Rusty Marlin]

The switches interrupt power to ground when the door is closed.
If you push it and the light dims, it means that a trickle of power is still getting though to ground.

 

[t00manyuserz]

If one or more of the switches is a problem, yes.

Sorry what I meant to ask was, if I take off all the switches, am I guaranteed the light would be off, and then I can add them back one by one and see where it fails?

The switches interrupt power to ground when the door is closed.
If you push it and the light dims, it means that a trickle of power is still getting though to ground.

So I possibly have a loose ground somewhere? That sucks awfully. I'm assuming I can't find where that would be without stripping half of the interior, so my best course of action is to just pull the bulb if testing each switch fails?

 

[gummycarbs]

Sorry what I meant to ask was, if I take off all the switches, am I guaranteed the light would be off, and then I can add them back one by one and see where it fails?

Do you want to get started diagnosing your problem, or do you want to ponder based upon assumptions?

So I possibly have a loose ground somewhere?

Opposite. The door switches connect the circuit to ground, so you have an unwanted ground somewhere.

 

[t00manyuserz]

Do you want to get started diagnosing your problem, or do you want to ponder based upon assumptions?

I do. What I meant to ask was, if I take off all the switches and the light is still on, do I learn anything from that state of affairs or not… but you’re right, I should just get to it and ask questions as I go along. I’ll take the four doors’ switches off tomorrow, hopefully it’s not the barn doors as I believe it’s inside the lock.

And yes. I phrased it wrong - my bad. By loose ground I meant something basically shorting somewhere and you confirm that - thanks. Hopefully it’s not that.

 

[jht3]

if you pull the B-pillar trim, you can unplug each front door switch. this will defeat the front switches. same thing as closing the doors. breaks the path to ground.

you're on your own for the rear doors. haven't messed with those personally.

or barn doors. the switch is part of the lock mechanism for tailgate models.

i guess if you wanted to get crazy, pull all the bulbs. test for continuity to ground at the +12 side of the interior light or door switch. EWD is your guide.

 

[clx16]

It may be possible that one switch is already unplugged and the connector is touching ground for you. The back doors are not hard just undo the bolt and pull the switch out. You won't have much wire to work with so put some tap around it and extend a little so you don't have to hold the wire while it tries to pull back in

 

[Captdone]

Check to see if your rear hatch/gate is closing tightly. The lock mechanism on my 94 FJZ80 was worn and not closing tightly and when I had my neighbor push on the hatch while I sat in the driver’s seat, the light went out. Now I’m looking for a replacement lock mechanism.

 

[t00manyuserz]

So I spent a tremendous amount of time cleaning the front switches only to get to the right rear one and find the cylinder part has disintegrated and was maybe shorting … so I taped around it to make sure no contact and opened up the rear left one … to find it has completely disintegrated and wire fell off and into the body somewhere. lol. So I’m going to guess my shirt is coming from there.

Going to order four new switches and see what I’m going to do with this. Pulled the light bulb from the instrument cluster for now so the battery at least doesn’t get wasted away.

Barn doors close well at least, so hopefully the mechanism is ok there.

 

[Rusty Marlin]

One of mine was smashed to smithereens too, that's the same problem I had with mine.

 

[jht3]

So I spent a tremendous amount of time cleaning the front switches only to get to the right rear one and find the cylinder part has disintegrated and was maybe shorting … so I taped around it to make sure no contact and opened up the rear left one … to find it has completely disintegrated and wire fell off and into the body somewhere. lol. So I’m going to guess my shirt is coming from there.

Going to order four new switches and see what I’m going to do with this. Pulled the light bulb from the instrument cluster for now so the battery at least doesn’t get wasted away.

Barn doors close well at least, so hopefully the mechanism is ok there.

why did you remove the cluster bulb? the lights in the door and headliner will still be on, no?

why not disconnect the rear door switches...seems they already are anyways? and tape over the connector/wires so it won't ground to the body anywhere. that way your remaining front door switches will still trigger the interior lights. what am i missing here?

 

[t00manyuserz]

why did you remove the cluster bulb? the lights in the door and headliner will still be on, no?

why not disconnect the rear door switches...seems they already are anyways? and tape over the connector/wires so it won't ground to the body anywhere. that way your remaining front door switches will still trigger the interior lights. what am i missing here?

Because I have to pull the trim panels to do it, since the wire has vanished - and I don’t want to just do it to fix the short. I flipped the ceiling light to “off” (inconvenient but what can you do). I’m waiting for the new switches to arrive before ripping the panels apart (and it’ll be a good opportunity to install the rear view camera too).

 

[60wag]

On my '96, the front light and middle light were on separate circuits operated by the front doors or the rear doors. I'd rather have any door turn on both lights so I tied them together. Are all of the 80s stock with 2 circuits? Never seen another car wired that way.

The switch in my hatch failed recently, now I can leave the hatch open without any lights on. I was going to fix it but now prefer it this way.

 

[wilson234]

Trying to trouble shoot similar issue. Door open light on dash and all door and dome lights on. Weird because it just happened all of a sudden. I took all the door switches out, ensured the wire and switch was not making ground to the door frame, unconnected the rear hatch switch (unplugged it) and still all lights on. I’m totally confused and out of ideas. Also when I removed the door switches I tugged on the wires, as I read some folks were finding out the switch wire was undone or disconnected.

Any ideas would be appreciated, now I have to pull all the door lights and turn off the domes so I do t drain my batteries.

 

[gummycarbs]

@wilson234 do you have an alarm? They pretty much always tap into the door switch circuit in order to trigger the alarm when a door is opened. They also sometimes tap into the same circuit for interior illumination when disarmed.

 

[BILT4ME]

Trying to trouble shoot similar issue. Door open light on dash and all door and dome lights on. Weird because it just happened all of a sudden. I took all the door switches out, ensured the wire and switch was not making ground to the door frame, unconnected the rear hatch switch (unplugged it) and still all lights on. I’m totally confused and out of ideas. Also when I removed the door switches I tugged on the wires, as I read some folks were finding out the switch wire was undone or disconnected.

Any ideas would be appreciated, now I have to pull all the door lights and turn off the domes so I do t drain my batteries.

When you say "ALL" lights on:

Did someone move the ceiling light switches to the "ON" position?

Because the front doors will illuminate the light above the back seat.
The rear doors and tailgate illuminate the rear cargo area light.

If you are getting BOTH, then odds are you have a short in the wiring in the ceiling and it is shorting both lights at the same time. Are the door lights coming on also?
What about the Map light?

 

[wilson234]

I do have an alarm, it was installed by prior owner. When I state all lights on, it’s both dome, all door lights. The map light is off, as I believe this light by the rear view mirror is not a light that can be door activated. it is really odd both front some and rear dome both seem to be on.

Interesting comment on the short, I’m thinking it might be the cause that makes the most sense. I went skiing recently and had the passenger side bench and rear seats up to store a few skis and snowboards inside the rig. The floor got a little damp from residual snow on the skis, are there any wire harness that run through this area? Also I did take the panel off next to your left foot and exposed the alarm system. It was not a pretty sight, lots of wiring tapping, a bit Mickey Mouse wiring, but I jiggled the wires around to see if anything was loose or maybe the lights would turn off, but no luck.

Just kinda odd, have owned the rig for 2 years and never had this issue, then all of sudden lights won’t turn off. Keep the ideas coming!!