Hi all,

On 850Ci built after 03/1991 there is no low coolant level warning anymore AFAIK.

I think I have the solution to cure this:http://forums.bimmerforums.com/forum/cid:906565711@08072008-0B45

Until 03/1991 the 850Ci had an expansion tank with a coolant level sensor (see attached pictures) which is basically a reed contact.
Part numbers can be found here:
http://bmwfans.info/original/E31/Cou/850Ci-M70/USA/L/A/1990/01/mg-17/ill-17_0081/

From what I have found out this sensor or better switch connects ground to pin 10 on the EKM in case there is enough coolant. If it drops below a certain level the ground connection of pin 10 is disconnected and a warning should go off in the OBC/MID unit.

I do have an 850 sitting in my driveway right now which has the appropriate expansion tank (must have been replaced once) but the sensor is disconnected. According to my findings I should get the warning now but I don't. But since this car is so screwed up I wouldn't be surprised to find a permanent ground connection somewhere in the car of Pin 10. So I'll have a closer look asap.

I'll let you know in case I have more info.

Cheers
Wolf

P.S. Schematics of the 91 850 can be downloaded from here:
http://shark.armchair.mb.ca/~dave/BMW/e31/ (http://shark.armchair.mb.ca/%7Edave/BMW/e31/)

http://www.wokke.de/BMW-E31-850Ci/PICT0014.JPG

http://www.wokke.de/BMW-E31-850Ci/sensor_coolant_level.jpg

Wokke, you're the man!

thanks a lot but I'm not there yet. I located the EKM today. It has three 26 pin connectors (green, orange and blue). I disconnected the blue one and got a bunch of various warnings in the MID so I'm on the right track. But I could manage to get a low coolant warning. I guess I need to do some more research and it is also possible that the car has been modified by a previous owner because the sensor was not connected due to the wrong connector.
I keep working on it.

Honestly,

If you do go through with this, please make sure the whole kit can be installed by a person who knows the basics. I really hate to mess around with the car if I don't have to:)

Honestly,

If you do go through with this, please make sure the whole kit can be installed by a person who knows the basics. I really hate to mess around with the car if I don't have to:)

I will - promised ;)