If your car is an E85, then you can get your wiring diagrams here. https://bmwteka.com/wds
To me, its is sounding like your Light Control Module (LCM) is playing up. You will need to scan it for trouble codes. This will need a scanner with BMW software.
Two options are:
1) Windows Laptop or Surface Pro, cheap special cable and BMW Standard tools. The tools come with the software to code another LCM to your car if you have to change it. BMW Standard tools are free from here. https://www.e46fanatics.com/threads/...tools.1274003/
2) Foxwell NT530 scanner with BMW software. Will help with the diagonistic's but will not code a LCM to your car. https://www.foxwelltool.com/wholesal...pin-cable.html You don't need the 20 pin connector for the Z4, but this listing is an example.
I see that you are in the UK. There is a very good UK Z4 forum here. https://z4-forum.com/forum/
1999 2.8L Z3 Roadster,
2000 3.0L Z3 Roadster,
There is only one thing more pleasurable than working on a Z3, that's driving it top down on a fine day.
Bookmarks