Firstfives.org

thought this might be of use ( maybe add to FAQ - TECH TIPS !)

As per link provided by RonDwyer for a e12 maintenance /repair manual, there is page showing process to diagnose ignition/spark no start issues.

https://www.bmwtechinfo.com/repair/main/057en/index.htm

https://www.bmwtechinfo.com/repair/main ... 057135.jpg

and

https://www.bmwtechinfo.com/repair/main ... 057179.jpg

note can scroll through numbers to get more info i.e. 057180-184 has troubleshooting charts



https://www.bmwtechinfo.com/repair/main ... 057180.jpg

https://www.bmwtechinfo.com/repair/main ... 057182.jpg