Door Ajar Light, Dome Light Won't Go Off (1 Viewer)

[travisimo]

So, I was at Windrock a while back and noticed my door ajar light kept intermittently coming on and going off, then it just stayed on.

Let me preface this with, yes i've looked at past threads but most of them end in the same place.

I've actually already had to replace a door switch before that broke so this isn't new to me.

I bought a new switch even though both the front ones seem completely fine (And one was practically new). Nothing.

I know it's the front because the back dome light actually turns off when you close the rear doors and the hatch)

My question is, what ELSE could it be? Could it be a relay or fuse? Something completely unrelated? This is driving me crazy!

 

[jonheld]

Interior lights are activated by grounding one of the switches. It's possible that you have a chaffed wire that is shorting to the body.
Have you tried removing both the front door switches and taping the wires?
There are no relays for interior lights, and if the fuse was bad you'd get nothing.

FWIW, I have an intermittent flash of the front dome light when making a hard left turn. This sometimes causes my doors to unlock. I have yet to trace it down.

 

[travisimo]

Interior lights are activated by grounding one of the switches. It's possible that you have a chaffed wire that is shorting to the body.
Have you tried removing both the front door switches and taping the wires?
There are no relays for interior lights, and if the fuse was bad you'd get nothing.

FWIW, I have an intermittent flash of the front dome light when making a hard left turn. This sometimes causes my doors to unlock. I have yet to trace it down.

That makes sense. I noticed when i pulled the Driver Side switch out the female connector literally "broke" off the wire. I had to take the interior door trim off to reconnect it. I knew it would need to be wrapped up but haven't done it yet so thats promising. Having said that, I would love to find a diagram of exactly how these switches work electrically since there is only ONE wire running to it. How does it even know when it's an open or close circuit?

 

[jonheld]

That makes sense. I noticed when i pulled the Driver Side switch out the female connector literally "broke" off the wire. I had to take the interior door trim off to reconnect it. I knew it would need to be wrapped up but haven't done it yet so thats promising. Having said that, I would love to find a diagram of exactly how these switches work electrically since there is only ONE wire running to it. How does it even know when it's an open or close circuit?

What year is your truck?

 

[travisimo]

What year is your truck?

1997

 

[Tools R Us]

... Having said that, I would love to find a diagram of exactly how these switches work electrically since there is only ONE wire running to it. How does it even know when it's an open or close circuit?

It's a switch to ground, the other connection is ground through the mounting screw.

 

[jonheld]

How does it even know when it's an open or close circuit?

The switch frame is grounded to the body. When the switch closes, the connection to ground is made and the circuit is complete.

 

[jonheld]

I would love to find a diagram of exactly how these switches work electrically since there is only ONE wire running to it. How does it even know when it's an open or close circuit?

Here is the schematic.

 

[travisimo]

So I just noticed on the passenger side when i press the switch in it slightly Dims the dome light but doesn't cut it completely off. Also, After i tried that, i went to the driver side and pressed the switch. it worked ONCE then didn't work again.

 

[jonheld]

So I just noticed on the passenger side when i press the switch in it slightly Dims the dome light but doesn't cut it completely off. Also, After i tried that, i went to the driver side and pressed the switch. it worked ONCE then didn't work again.

Why don't you simply remove the switches from the circuit. If the light stays on, then you know it can't be the switches and have a short. Or if the light is off, then you know you have a bad switch.

 

[travisimo]

Why don't you simply remove the switches from the circuit. If the light stays on, then you know it can't be the switches and have a short. Or if the light is off, then you know you have a bad switch.

Forgive my ignorance but are you saying, if the switched are disconnected entirely the lights should stay off?

I considered that but based on my logic It seems that the default state of the switches is "on" meaning if they're not being pressed in by the door then the lights stay ON. Would them being disconnected not be the same as them also not being pressed in?

 

[jonheld]

Forgive my ignorance but are you saying, if the switched are disconnected entirely the lights should stay off?

I considered that but based on my logic It seems that the default state of the switches is "on" meaning if they're not being pressed in by the door then the lights stay ON. Would them being disconnected not be the same as them also not being pressed in?

When the door is closed the switch is open and there is no ground path so no light. When the door is open, the switch is closed and there is a ground path, so the light comes on.
If you remove the switch, there is no ground path because the circuit ground is the switch frame.

 

[travisimo]

When the door is closed the switch is open and there is no ground path so no light. When the door is open, the switch is closed and there is a ground path, so the light comes on.
If you remove the switch, there is no ground path because the circuit ground is the switch frame.

Boy wish i had been smart enough to know that before i ordered a replacement switch. Unplugged both of them and the dome stays on. Now, i have absolutely NO clue where the short could be. UGH

 

[Malleus]

Don't fret, you can always use a replacement switch. Chances are your wiring insulation is chafed somewhere at a pinch point. Look over the location and wiring diagrams and try to locate those chafe/pinch points. It's unlikely the failure is in the middle of the run somewhere. That'll cut down on the number of possible locations for your first run at the problem.

If you decide you absolutely don't want the switch, PM me. I'm in need of one and I'll take it off your hands.

 

[landcrshr]

Are you experiencing any other issues? Intermittent clock? Radio losing memory?

Believe it or not, the "on-but-dim" dome light scenario can be caused by an OPEN circuit.

I've seen this before and it was related to a faulty wire junction for the "DOME" circuit, possibly caused by a leaky windshield.

The "J3" junction shown here:

For an explanation of how this is possible, this diagram shows how current could flow through the dome light when there is a break in one of the wires.

 

[bcart1991]

Mine has this problem too (kinda).

My door isn't pushing my switch in enough to fully open the switch. My plan is to glue a few washers to build up that small area of the door where the switch hits. Hopefully that will cure it, since the switch opens fully when I hand-press it in.

 

[travisimo]

Nothing else is wrong... Clock is great, radio is solid, no other dash issues. I jumped the wiresin the b pillars to the truck and i got the same dimming on the passenger side but nothing on the driver.

The DS has clearly been replaced before by a PO, Then it broke and I replaced it with a spare from a parts cruiser that was basically brand new... This time when i pulled the switch to replace i had clearly been too rough with it on my previous repair and scarred up the wire and almost severed the female connection off the wire completely. I reconnected it and taped up with wire so I really don't think it's up in the pillar...

Aside from that I can only recall when It actually went out on me. I was literally driving on a trail at windrock but it was relatively dry. it was intermittent at first but it wasn't long and it was permanent. I'll have to follow it one day when i get time I guess.

 

[gummycarbs]

My plan is to glue a few washers to build up that small area of the door where the switch hits. Hopefully that will cure it, since the switch opens fully when I hand-press it in.

How about some adhesive rubber bumpers? They come in all shapes and sizes, and rounded or flat profiles.

Liberty Self-Adhesive Bumpers (24-Pack)-490801 - The Home Depot

 

[travisimo]

Under the lights' clear cover, there's a metal strip carrying 12V that pas


How about some adhesive rubber bumpers? They come in all shapes and sizes, and rounded or flat profiles.

Liberty Self-Adhesive Bumpers (24-Pack)-490801 - The Home Depot

yeah i wish mine was that easy lol

 

[BILT4ME]

Be aware that Toyota switches the GROUND side of the circuit, whereas, MOST domestic vehicles switch the HOT side of the circuit.

Toyota:
HOT.....LOAD.......SWITCH.........GROUND

Domestic:
HOT.......SWITCH.......LOAD......GROUND

If the light is staying ON with the switch disconnected, the wire between the switch and the light is grounding itself SOMEWHERE.

Could also be the light body itself with that switch. Maybe the fixture itself is having an issue.