I have an old beetle VW (dutch: Kever, German: kafer) and I took the K3500 kit to hold on the Interior ligts for a few seconds.
When I Switch off my (screen) wiper, the Interior light switched on…
I tried a few condensator / capacitator
Anyone an idea what kind of capacitator I must use ?
Probably, you will need a very large cap (e.g. 4700µF).
Today I bought a 4700 uF Cap and connected it between 12V and massa, but no glue. When I switch of the Wiper, my inner light swithed on.
Apparantly, the wiper motor generates excessive noise, which triggers the circuit.
You could try adding extra filter caps to the wiper motor.