Interior light and window switch problem

[chu346]

Since I have own my car the interior interior light doesn't switch off from shutting the doors and the window switches don't work when the drivers door is open, but they do when the passenger door is open.

Any idea what the problem is?

Car is a 1992 318i convertible.

Thanks

[viz007]

I had the same issue with mine and someone here told me how to work it out. Test the door switches one by one on both doors by pressing the switch shut with your finger rather than closing the door. If the light switches off like with mine everything is ok and the problem is simply a little black plastic spacer which fits on the door and contacts the switch when the door closes has fallen off.

Part number 61311370695

[chu346]

Nothing happens when I press the switch. The light stays on

[viz007]

Do the lights on the electric window switches stay on too?

[chu346]

No.

They come on when ignition is on or if passenger door is open but not drivers door being opened.

[Brianmoooore]

Remove the driver's side pin switch from the A pillar (single self tapping screw), and tell me exactly what colours the two wires connected to it are. Don't worry about the odd minor spark that you may see while doing this.

[chu346]

Sorry you'll need to click the link

[Brianmoooore]

Can't make out the colours for sure from the pic., but if one of them is a brown/yellow (should be on the second switch terminal), then you have an interior light switch off delay module fitted.
Does your central locking work properly?
Pull off the brown/blue (if that's what it is) and touch the end of it against paint free body metal - the edge of the hole for the self tapping screw should do. Do the window switches light up?

[chu346]

Central locking seems to be ok. It was struggling to open and close about a week ago on a cold morning though.

Brown blue wire when grounded solves the window switch problem. The door switch is crusty and some of it broke away as I tried to clean it up. That me have been the reason why it wasn't grounding the brown/blue wire.

Brown/yellow wire wasn't connected. I think the wire that was connected is brown/purple?

[Brianmoooore]

Brown/purple is indeed the wire that should be connected if you don't have a delay unit fitted. The brown/yellow should be doubled back and securely tied to the loom if not used, so it looks like someone's been messing.
Take out the switch on the passenger's side as well, and disconnect the brown/purple on that as well. If the dome light still stays on with both brown/purples disconnected, then it looks like the 'someone' has been messing with the light wiring as well.
Your switches look to be a different shape than the ones I'm familiar with, and mine are made of stainless steel, so no chance of rust. They do have a long term problem though, where a sliver of black plastic eventually gets scraped between the contacts. Easily removed in seconds with a craft knife, then good for another twenty years.

[chu346]

Had a quick clean up of both the switches and at the light I've got a positive and negative wire. The third wire is a switched positive that turns on when the doors are shut. Is this normal?
.

[Brianmoooore]

Take out the switch on the passenger's side as well, and disconnect the brown/purple on that as well.

Done this yet?

The wires at the bulb are a red/green (permanent live) which is permanently connected to one side of the bulb, a brown (earth) and a brown/purple (which goes to the door switches). These latter two are connected to the switch.
All switching is in the negative wire.

[chu346]

I have taken the brown/purple wires out of each of the doors and get no signal at the light end.

[Brianmoooore]

If the light goes out with both brown/purples disconnected, then they are being earthed by a pin switch or pin switches, even when the doors are closed. The switches are of a very simple construction, and it's difficult to see how they could not break the circuit when the pin is pushed in. Check that the plastic buttons on both doors, that actually push against the pin when the door is closed, are both present.

[chu346]

Plastic buttons are in place and work fine.

When either door is open the interior light gets a no signal. When they are closed the light gets a positive signal.

Where do all these wires go? Do they go to some kind of signal box?

[Brianmoooore]

You're over complicating this. It's a VERY simple circuit, and all I want to know is whether the bulb is lit or no. The wire is all there is.

[chu346]

My car is a convertible and the interior light is a joke so I am using an e46 lamp. When I got the car the bulb was blown so I don't know if there was an issue there before or not.

The 2 outer map reading lights are connected to the constant wires and have their own switches. I want the switched wire to turn off the central light when shut the doors and turn on the light when I open a door. It currently works the other way around so the light comes on when I shut the doors.

[Brianmoooore]

I am using an e46 lamp.

Don't you think this little nugget of information might have been useful if mentioned in your OP??????!

You'll need to investigate the possibilities of reversing the constant live and earth to the light, so as to convert it to 'earth to operate'.

[chu346]

I didn't think it mattered as the issue is the wiring doesn't seem to do what it is meant to..

I have bypassed the e46 lamps wiring and need the wiring to either give me 12v+,12v- & a switched wire when I open a door. Is that not how the stock wiring and lamp works?

BTW I have been testing with a multimeter

[fixedwheelnut]

Here is a diagram for a 92 convertible that should help, 12 volts comes in from Fuse 21 via the bulb/lamp unit and if in door open position should earth out the bulb via the door switch when the door is open.
If you measure the Brown/Violet wire with a multimeter it will read 12 volts if the bulb is good as it is not switched, earth that wire out the bulb should light.


Here is a useful link to the ETM manual
http://wedophones.com/Manuals/BMW/1992% ... Manual.pdf

[Brianmoooore]

The interior lights (along with other things) on an E46 are controlled by the ZKE module - a computer probably containing at least a 1000 times the entire electronics in a complete E30.
The door pin switches just feed a signal to this computer.
Contrast this with the non delayed dome light circuit that is shown above, where the switches control the light directly.
There's nothing wrong with your wiring - you're just doing the equivalent of dropping lumps of coal into the fuel tank, and expecting the engine to run on them.
Having said that, I think the E46 light (which I think is similar to an E39 light) can be reconfigured to work with the E30 loom.

[fixedwheelnut]

The interior lights (along with other things) on an E46 are controlled by the ZKE module - a computer probably containing at least a 1000 times the entire electronics in a complete E30.
The door pin switches just feed a signal to this computer.
Contrast this with the non delayed dome light circuit that is shown above, where the switches control the light directly.
There's nothing wrong with your wiring - you're just doing the equivalent of dropping lumps of coal into the fuel tank, and expecting the engine to run on them.
Having said that, I think the E46 light (which I think is similar to an E39 light) can be reconfigured to work with the E30 loom.

I just realised he was using an E46 lamp, try this link you need a programmed IC unit to make it work
http://www.bimmerforums.com/forum/showt ... -E36/page2

[chu346]

Thanks for all the help, I have got everything working correctly. There was a problem with the drivers door switch that was causing the windows and interior light to not work properly. After getting the window switches working I was testing the interior light wiring with a multimeter which gave me readings I didn't expect and confused me. The constant earth when connected to the door switch wires shows -12v on the multimeter.

The reason I didn't say about using the e46 light was because it is wired in the same way as the standard light.

[chu346]

I'm very happy with the results