Those dang dome lights!

[Nick Triesch]

I have fixed almost everything on my Carrera since I bought it two years ago. Fixed clock with new caps, fixed speed control with new computer, fixed A/C, and fixed the central locking! But I can't fix the dome lights. I have new door switches, I have a good ground because both lights turn on in the "on"position. Door switch is good because door buzzer works when door is opened and goes off when closed. . But lights will not go on when door is opened and switch is in the door positin. Does just one wire go to the door switch or two? Up at the dome light I have two wires going to each light. Is this correct? I cleaned everything. Maybe new dome lights? Drives me crazy! Thanks, Nick

[JAR0023]

Not sure if this'll help or not but I've been inside my dome lights recently.

Three positions. Press the front for on. Press the back for off. Centered and 'flat' is the on with door position.

I also have two wires going to each dome light. IIRC the dome light chassis grounds on the roof sheetmetal. I think(can be dangerous) this is for the jamb switches to work. Could be your headliner is in the way.

I have one wire going to the door jamb switches, or at least to the passenger side as that's the only one I've had apart. My passenger side door open would result in flickering lights so I pulled it out and cleaned up the contact area.

Do you have a Bentley with wiring diagrams?

-J

[donagain1]

To quote the classics, "Verrrrry Interesting!... My center (flat) position is "Off".

12V gets to the fixture on the solid black from fuse #1 on the ten position block. The door-switched ground gets to the fixture on the brown/white. The constant "On" ground is the solid brown to the frame. If you're in a coupe, one of the fixtures has double the amount of wires so it can daisy chain to the opposite side fixture.

[DRACO A5OG]

Oh Nicko,

Next time I am down there I'll stop by and fix it for yeah :-)

In the meantime don't worry about and enjoy your baby :-D

Jim

[Nick Triesch]

Thanks Jim! Next time you are down San Diego way. What is cool is that the dome lights and the engine bay light are the last of the things to be fixed! .......Well, not quite true, speedo pops into action a bit late. Always something! Nick

[tirwin]

Seems like I remember reading about a similar problem Joe Bob had a while back. Might try searching for that thread. I can't remember what the fix was.

[Joe Bob]

Door switch fix.......need a BTDT opinion

[yel911]

My dome light was out in my 993 cab. First, I replaced the bulb, then the fuse. Now, I realize that the glove box light is out!!! But why a fuse??? Also, since I replaced the fuse (turned this circuit on) I think it's draining my battery.

[Concestor0]

I hope you don't mind me borrowing this thread to get some feedback on yet another electrical/dome light puzzle.

My brown/white wire is showing 12 volts and no ground. The black wire also has power going to it (as is the norm). Without a ground to the door switch i don't have a door activated light but the manual ON works just fine. It's the same situation for both sides.

Both door buzzers work just fine also.

Anyone else had this situation - power from a ground wire?

[Chuck.H]

Are you sure it's supposed to be a ground? I thought it picked up ground from the contact with the body when it's installed, and one wire was full time power (for the always-on mode) and one wire was for the door switches...

I don't have my wiring diagrams handy to confirm this though.

Chuck.H
'89 TurboLookTarga, 341k miles

[86 911 Targa]

Originally Posted by Concestor0

I hope you don't mind me borrowing this thread to get some feedback on yet another electrical/dome light puzzle.

My brown/white wire is showing 12 volts and no ground. The black wire also has power going to it (as is the norm). Without a ground to the door switch i don't have a door activated light but the manual ON works just fine. It's the same situation for both sides.

Both door buzzers work just fine also.

Anyone else had this situation - power from a ground wire?

Here's the circuit from my owner's manual for the coupe, targa, & cab.

Good luck,

Gerry

[Concestor0]

Thanks Chuck and Gerry, the way I understand it is that there is one power source (black wire although indicated as "SW" on Gerry's schematic), a constant ground through the frame at the housing for ON position and ground at door switch for door light. This would make the most sense but, then again, i'm not German.

The BR/WS wire in Gerry's diagram comes from the door switch which seems to be a ground?

[kidrock]

constant ground is supplied to the fixture when properly installed into its metal housing.

[Concestor0]

Interesting...I just went out and switched the BR/WS wire with the SW(black) wire and tried the manual ON position and the light would come on but at roughly half brightness.

[Blackie911]

Actually I removed the drivers side bulb. This because a couple times i accidentally rubbed it with my head while exiting (993tt) leaving the damn light on and once draining the battery! I leave the passenger side alone and have a small flashlight in the drivers door pocket.

[jbd3]

I have exactly the same symptoms in my '86 930. door switches work enough to start buzzer, lights come on manually, no-go on on-with-door. Did you ever get a fix to this?

[BesideTheBox]

I realize that the post that I'm replying to is from nearly 11 years ago, but keep reading.
I have had the exact same interior dome light issue/behavior since 2005, so for roughly 18 years. And it didn't work for the previous (2nd) owner either.
Two days ago, I FIXED this issue by cleaning the grounding point on the left hand side of the engine bay forward of the coil and fuel filter in my '86 Carrera.
Unbolt the grounding nut, clean it and the 3 copper grounding rings attached to it with fine steel wool and tighten it all back up.
Works perfectly now. I hope this helps you and anyone else with this issue.
BTB

Originally Posted by Nick Triesch

I have fixed almost everything on my Carrera since I bought it two years ago. Fixed clock with new caps, fixed speed control with new computer, fixed A/C, and fixed the central locking! But I can't fix the dome lights. I have new door switches, I have a good ground because both lights turn on in the "on"position. Door switch is good because door buzzer works when door is opened and goes off when closed. . But lights will not go on when door is opened and switch is in the door positin. Does just one wire go to the door switch or two? Up at the dome light I have two wires going to each light. Is this correct? I cleaned everything. Maybe new dome lights? Drives me crazy! Thanks, Nick