IHKA Repair?

[hooutoo]

Happy New Year All!

I have a '94 850ci and have been reading the many many posts on the subject of heating (drivers side is always warm) and cooling problems and how they relate to the IHKA module. I have already replaced the heater control valve (hcv) after completely tearing apart the old one. It was totally correded and WAY beyond repair. That didn't work! This problem is to the point where my batteries are completely drained in 2-3 days. At this point am pretty sure it's the IHKA control module (bosch 9140010000). Their is a lot of info here concerning how to replace ICs and resistors and such but I'm looking for someone who can actually do it???? If you already have a spare repaired one I will gladly send you mine plus $ and you send me yours if that works?

I live in South Florida and absolutely no need of a heater in the first place since it's warm here year round. I'm also looking for a temporary solution to just disable the heater function completely until I can get a my IHKA module replaced. I'm mean once the car warms up it's like a sauna inside.

Any help would be greatly appreciated!
Steve

[Timm]

Frankie has been through this and has done this write-up:

http://www.frankies-bmw.com/8series/...ter_valves.php

[hooutoo]

Frankie has been through this and has done this write-up:

http://www.frankies-bmw.com/8series/...ter_valves.php

Thanks for the info Timm. This problem seems to be the bane of this car’s existence. SOOOO many people on the e31 forum have experienced some form of the heating/cooling problem. Thanks to EEDegree who gave me some tips to try to narrow down where the problem lies. So, when I pulled the old HCV I didn't really inspect the old male side of the plug. Mine was so corroded that the connection points inside of the plastic casing just came out. This actually made it easier to follow EEDegree suggestion and connect some alligator clips on those plug post attached to a couple of old tail light bulbs to see if any power was coming into the HCV. Unfortunately, NADA! Absolutely no power at all! I also tested with a multimeter to confirm. At this point I’m going to bypass the heater core completely while continuing to trace the problem upstream. I guess the next stop are the switches behind the temperature thumb wheels. Correct me if I’m wrong but after that comes the IHKA control module itself???? This is REALLY frustrating as my 850ci only has 70k miles on it.

[Timm]

[shogun]

Training manual IHKA E31, 37 pages for download https://www.slideshare.net/slideshow...trol/153541854

[cartoonz]

Training manual IHKA E31, 37 pages for download https://www.slideshare.net/slideshow...trol/153541854

Nice... but cannot download without subscribing? Send me a copy and I'll upload it to MWrench

[shogun]

I am also not registered there, maybe some already downloaded it and can send you, would be nice if you can upload it to MWrench site, thanks.

BTW: I found that the stepper motors on E31 IHKA are same p/n's as used on E30, E36, E34, E32, so if someone needs a stepper motor for his E31, check cross reference of p/n

[Timm]

I have a copy here: https://www.meeknet.co.uk/e31/IHKA.pdf

[LappingLuke]

Wow that is a nice document!