Troubleshooting basic module GM-II (E)

Troubleshooting basic module GM-II

When is my basic module defective?

This manifests itself in malfunctions in:
- Central locking system
- Window openers
- Windscreen wiper & contact pressure control
- Sunroof
- Anti-theft alarm system
- Washers and headlight washer
- Interior light
- Control of the relay module ....
as well as sporadic twitches which manifest themselves in independent opening of windows, sliding roof or the boot lid.

How can I test this?
The easiest way is to open the trunk of the 8-series.
-> The trunk light should then burn.
Now all doors (trunk remains open) and complete the vehicle.
-> goes out the trunk light after 15 minutes, the basic module is so far in order.
-> remains the trunk light on, this indicates a defect of the basic module.