Problems Internal light control

Hello, everybody.

Recently I built 4 times footroom lighting additionally to the inside light, thought LEDs are no problem.

Has worked wonderful for a few weeks until one day the
Interior lighting
ZV
Alarm stopped working.

Locked by... replaced, ...... 2 days later, through again.... Replaced again... then the drive at once goes on the light inside, switch without function....Zündung from key out ZV to ...also no reaction. then after 2 km she goes out again ????
The day after then she never wanted to go out again ?? :-)

As successful is :
Since then I have neither ZV nor interior light, nor alarm, because I always have to pull the fuse when I leave so that the whole doesn't burn all night.

Guess I killed the ECU through the LEDs...

Now my question

I heard this is all controlled by the alarm control unit? Is that true? Or what could have been a short one?

If it's DWA ECU, where exactly is it?

PS terminal of course then the LEDs off again ...because so it just annoys.

LG Gerald