Interior light comes on while driving

[alexpc]

My ‘08 Polo has a strange issue with the interior lights. When set to the ‘on when door open’ position, they will randomly come on while driving. This is also combined with them staying on while the car is locked sometimes, and also while locked the hazard lights will randomly flash, or sometimes stay on constantly (whether the interior lights are on or switched off).

The thing is, this is only an issue during winter when it’s colder outside. In warmer weather it’s fine.

I’ve seen that it might be the door switch (though not sure where that is, is it part of the door lock actuator? If so, I replaced the passenger one a couple weeks ago due to the original one failing, so would leave either the drivers or boot? It’s a 3dr.) however some have said it’s the wiring between the door and body, or the interior light module.

Any ideas?

[Maarten]

Could be a faulty microwitch, system thinks door is open.
Does the open door symbol light up in the cluster when that happens?

[alexpc]

Could be a faulty microwitch, system thinks door is open.
Does the open door symbol light up in the cluster when that happens?

I've never noticed a door open light on the cluster. Is the microswitch part of the door lock assembly? If so its probably easier to replace the whole thing instead of just the microswitch (and also prevent the original door lock from failing). It would make sense with the hazards flashing if that switch has failed and the car thinks the door is opened when its meant to be locked.

[Maarten]

This door open symbol

Screenshot_20231110-185523.png (4.1 MiB) Viewed 1296 times

Do you have factory alarm?

[Maarten]

There are more microswitches in the lock.
Replacing complete lock is easier then replacing individual switches.

[alexpc]

Screenshot_20231110-185523.png

Do you have factory alarm?

It doesn’t have that icon on the cluster.

Not sure about the alarm, it has a red light on the drivers door that flashes while locked but never heard an audible alarm go off in the 5 years I’ve owned it.