Door Switch Driver Side (Left) Interior Light

Dear members,

When opening the driver's door, the interior lights no longer turn on, but they do work on the other doors. Strangely, a warning sound is emitted when the lights are turned on.
Is anyone aware of the error?
Where is the door contact switch located?

Thank you very much.
and best regards,

I'm having the same problem.
The door contact switch is located directly on the door lock! To access it...
You have to remove the entire interior trim, which is a thankless job. However, the door contact switch is not the problem; it works perfectly in my car. Otherwise, the warning horn wouldn't function. My suspicion is that the ground cable, which runs from the door lock switch to the interior lights and also the warning lights in the doors, is pinched and damaged inside the door bellows. So far, I haven't been able to locate the exact problem.
If anyone has already fixed this error before, I would also appreciate some advice, as I am about to .

Dalitroll wrote:

... When opening the driver's door, the interior lights no longer turn on, but they do work on the other doors. Strangely, a warning sound is emitted when the lights are turned on. Is anyone aware of the error? Where is the door contact switch located? ...

... which car/year of manufacture?

I'm experiencing this problem with a Golf IV TDI, 2-door model, manufactured in 1999.
Best regards, PIT!

Could the error have the same cause as described by Michael here?
/viewtopic.php?t=1870&start=0&postdays=0&postorder=asc&highlight=interior%20lighting

But then the interior lighting wouldn't work when the passenger door is opened, would it?

TDI PIT wrote:

I'm experiencing this problem with a Golf IV TDI, 2-door model, manufactured in 1999!

Hi,

Okay, the Golf IV has the contacts for the doors integrated into the locks. So, like with many other cars, one of the microswitches in the door lock is likely defective. The only thing to do is to measure it.
I've experienced this same issue with the rear hatch lock and the passenger-side door before (and this was on a 2002 model!).

No, Bertil!
You're wrong; I already told you that I checked the contact switch, and it's perfectly fine! It works flawlessly!
The problem is not in the switch!

TDI PIT wrote:

You're wrong; I already told you that I checked the contact switch, and it's working perfectly fine!!! It functions flawlessly!!! The error is not in the switch!

...just because the indicator light turns on doesn't necessarily mean the switch is working correctly!
The indicator light is directly connected to the door switch, while the interior light is connected to the switch via a blocking diode. If the blocking diode is defective, the indicator light will work, but the interior light will remain off!
Does the car have position lights in the door? If so, do they turn on when the door is open? If not, then you are likely correct in your assumption that the problem is with the wiring to the interior light. The position lights are connected in parallel with the interior light.

I had already said: The only thing that helps is to measure.

You're wrong; I already told you that I checked the contact switch, and it's working perfectly fine!!! It functions flawlessly!!!
The error is not in the switch!

...just because the indicator light turns on doesn't necessarily mean the switch is working correctly!
The indicator light is connected directly to the door switch, while the interior light is connected to the switch via a blocking diode. If the blocking diode is defective, the indicator light will work, but the interior light will remain off!
Does the car have position lights in the door? If so, do they turn on when the door is open? If not, then you are likely correct in your assumption that the problem is with the wiring to the interior light. The position lights are connected in parallel with the interior light.

I had already said: The only thing that helps is to measure.


'But the locking period only applies to cars without the comfort system!'

Yes, I have position lights. Both of them work, but only when the passenger door is open. They don't work when the driver's door is open, and the same applies to the interior light!
Since I have a base model, I don't think it has any comfort features.
I couldn't detect a blocking diode on the switch either.
Best regards, Pit!

Hi,

If position lights are present and there is no comfort system, then the blocking diode is also installed. Otherwise, the warning buzzer would also sound when the passenger door is opened.
The blocking diode is located somewhere within the wiring harness of the door (I haven't checked it on a Golf IV yet).
If the side marker light doesn't work when the driver's door is open, then the problem must be in the door itself. The cable runs from the switch, through a blocking diode, to the side marker light and also to the interior light. Only the cable to the interior light leaves the door. If both lights (side marker light and interior light) are not working when the driver's door is open, but the audible warning chime is working, then the defect should be relatively easy to locate!
The only thing that will help is to use a multimeter to test the wiring harness in the door.