Door Wiring for the Dome Light?

[ClayW]

What wiring is in the driver's door that affects the dome light?

When I open the driver's door on my 1991 325i four-door, the dome light stays on only for the first third of opening, then shuts off. If I jiggle the harness between the door and the body, the light will come on.

What wires should I be inspecting for breaks?

[StereoInstaller1]

You should be replacing the switch, or at least take it apart and scrub the contacts

[StereoInstaller1]

There are no domelight wires in the door itself at all...but it is likely that you are jiggling the wire on the other side of the door jamb, causing the switch to make contact

[DRTSRFR]

I have the exact same problem...

...but it's not the switch.

When I have the door all the way open, I can lift the harness between the door and the jam and the light comes on until I let go. If I hold it the light will stay on.

This leads me to believe it's the pin connector in the jam.

[StereoInstaller1]

...but it's not the switch.

When I have the door all the way open, I can lift the harness between the door and the jam and the light comes on until I let go. If I hold it the light will stay on.

This leads me to believe it's the pin connector in the jam.

Mark, it is. Yours is the red wire that loops through the door lock system, the "unlock disable" circuit. Clean your harness with CRC and pipe cleaners, I bet it fixes all of it.

Or, disable that stupid circuit by connecting the 2 red wires in the kickpanel, behind the speaker.

Luke

[ClayW]

Mark, it is. Yours is the red wire that loops through the door lock system, the "unlock disable" circuit. Clean your harness with CRC and pipe cleaners, I bet it fixes all of it.

Or, disable that stupid circuit by connecting the 2 red wires in the kickpanel, behind the speaker.

Luke

Two Questions:

1. What is the red wire modification that I see referenced so much and how does it change the function of the power locks?

2. What is CRC? Otherwise, what is the best way to clean a harness and the connectors?

[DRTSRFR]

CRC= http://www.crcindustries.com/ei/cont....aspx?PN=03070
Contact cleaner.

Already sprayed and cleaned it Luke. I think it's a loose pin barrel.

[hendrixvodu]

I bet you the screw backed out holding the striker switch happened to me on 3 different e30's tighten the screw the holds the switch

[StereoInstaller1]

I bet you the screw backed out holding the striker switch happened to me on 3 different e30's tighten the screw the holds the switch

No, what he is talking about is rarely seen on car that came wit a roof.

There is a pair of red wires going in and out of the door that provide power, through a switch, to the dome light and door lock relays.

Why the hell BMW would run power for something as critical as door locks through the door is just weird as hell to me, but they really wanted to kill all power to that circuit, obviously.

Luke

[hendrixvodu]

Thats strange ive never even heard of that. is it a late modle thing? ive been trying to track down a problem with my brothers car for a non working drivers door light switch so far ive got a dead relay and a missing cental locks relay, tried a working light relay and still no good apparently they use the central locks relay with the light relay? idk why on earth they would link the 2 together

[StereoInstaller1]

the only link is the power, and I have only seen this stupididty on cabbies after '90

[hendrixvodu]

haha well that explains when my 88 doesnt have it and im sure my brothers 92 vert does, I just bypassed my brothers for now by taking the purple wire that runs up to the dome "it was plugged into white plastic conn in the kick pannel" unpluged it from the conn and connected it to the door striker, would that work for the OPs problem?

[ClayW]

While I was in there....

I'll get the proper cleaner and do the red/black wire trick. I'll report back the results.

While I was in there, I found a few unconnected wires. Should these be connected to anything?

[ClayW]

I figured it out.

Apparently, the dome light functions in tandem with the central locking system. After cleaning the contacts in the door harness to no avail, I bit the bullet and sliced open the door wiring sleeve. I found that the infamous red/black wire was broken, but making intermittent contact with the loop. When I bridged the two ends, the central locking computer clicked on and the dome light came on. I have no idea what the functional or electrical relationship is between the two, but the central locking computer seems to need to be working to let the dome light come on.

In the door sleeve:



I did the red'black wire fix and all is well. I imagine that most red/black wire fixes were done thinking that the connector was the problem when the wiring was actually breaking.

[StereoInstaller1]

Apparently, the dome light functions in tandem with the central locking system.

Well, the power for both is that wire, so in that regard, yes, they are in tandem.

Good to hear you got it back up and running!

Luke