Courtesy Light not working

[MOLLYTHEVIKING]

Hi guys,

I'm hoping someone can help me with todays little conundrum. I am looking to add some low level LED's to come on when the sliding door and drivers door is opened. The interior light works fine but when it is switched across to work with the courtesy light nothing seems to happen ?!?

I'm not sure if it is a wiring problem or something wrong with the light.

Once i've worked this out I can look at connecting up my 12v LEDs ( which is another head scratcher at the moment)

Here is a photo of the wires running into the interior light. Any help would be greatly appreciated

Thanks

Clive

[CJH]

The interior lights work by switching the earth side of the light. There's a permanent live (your red wires) and a permanent earth (the terminal with two brown wires, and then there's an earth which is switched by the door switch (the single brown terminal). The door switch often gets corroded, and can be cleaned up, but they're cheap to replace. Make sure that the single brown wire is still connected to the back of the door switch. Also make sure that when the light switch is in the 'door switch' position it makes contact with the single brown terminal.

If you want to make sure all the courtesy lights come on whenever any door is opened you need to run a wire to link all those 'door switched' earths.

[ghost123uk]

DOH = beat me to it

That looks OK. The "switching" is done via the brown cables which are the "earths" The lamp is "live" all the time via the red wire. One brown wire goes to the door pin switches and when the door is opened the pin switch earths the brown wire, hence turning the light on.

So, 2 things to check. It is common for the tiny brass contacts in the light to arc and wear down and also loose their springyness. So you need to check those contacts (around the 2 brown wire spade connectors. New lights are cheap and easy to obtain. (VW Scirocco MKII ones ~1985 to ~1992) are the same and I think MKI and MKII Golf ones are too).

Next, and again quite common is for the pin switches to be not working. They come off easily with 1 screw but be careful when extracting the switch that the wire (with a small spade connector on it) does not fall off and drop down the A pillar. Not the end of the world, but a faff to get it back out of the small hole. Now, you can test the switch by simply connecting a short length of wire from a good earth to the brown wire (spade) on the pin switch (you cannot get a shock, so you can just hold it in place with your fingers). If the light then comes on then it is the pin switch at fault. The little contacts in the pin switches can get burnt by the slight arcing that occurs = clean them up.

[CJH]

DOH = beat me to it

Hehe - that's cos you wrote the better answer

Clive - a quick is fix is often to 'ping' the door switch in question. Push it in then let it ping out - do it a few times. This is sometimes enough to clear enough of the corrosion to allow it to earth properly. Not recommended as a permanent fix, but it doesn't require any tools!

[MOLLYTHEVIKING]

Thanks guy's,

I will take a look after work to see if I can get it working for now. I can then look at wiring up the LEDs to make sure everything works, before fitting new switches and tidying up all the wires. That's the theory anyway!

I may separate the front and rear LED's and perhaps fit a switch in the back so that the LED can be turned off if the sliding door is open for a long period of time.

Cheers

Clive

[CJH]

I may separate the front and rear LED's and perhaps fit a switch in the back so that the LED can be turned off if the sliding door is open for a long period of time.

I used a switch from RS that has two different 'on' positions and a central 'off' position - just like the courtesy lights themselves.



I used it in my rear headliner lighting, which I posted about here and here

When I started out on this mod I was given some helpful pointers in this thread.

[MOLLYTHEVIKING]

So, I've wired an LED strip light up in the footwell which activates with the drivers door courtesy light (now fixed). Only thing is at the moment I cannot turn it off with the courtesy light. So basically it will ALWAYS come on when the door is opened even if the switch is off. I have linked one wire to the switch it the door and the other to the power into the original light. I'm sure there is something glaringly wrong with what I am doing.....

[CJH]

The original cab courtesy lights have a three position switch: 1-on, 2-off, 3-controlled by the door switch. Position 1 routes the negative side of the bulb direct to earth, position 2 breaks the circuit, and position 3 routes the negative side via the door switch. The cable that you've added from the negative side of your new light to the door switch is the equivalent of position 3.

Like this:


If you want your new light to be controlled by position 1 and 2 as well, that's more complicated. You'll need to route the negative from your new light into the cab courtesy light switch, like this:


I'm not sure though, from memory, whether this is possible with the cab courtesy lights. Pull one out and take a look - it should be fairly clear how the switch position works, and you should be able to tell if it's possible to connect at the point I've indicated in the diagram.