Climate/IHKA control not working, what are my options

[jgold47]

My auto button seems to be broken. I can pull the unit apart and try to clean/resolder it, but I was looking at just grabbing another unit to replace mine.

I assume there is no difference on facelift IHKA units?

Having said that, I'm wondering what would happen if I plugged:

BMW E38 Climate Control 1995 2001 740i 750iL 760 AC Heater Ihka 6411 8 385 592 | eBay

in?

[Qsilver7]

Originally Posted by jgold47

My auto button seems to be broken ... I was looking at just grabbing another unit to replace mine. I assume there is no difference on facelift IHKA units?

Having said that, I'm wondering what would happen if I plugged in?:

E38 IHKA

E38 IHKA w/MAX button



(e39/e53 IHKA w/MAX button)

It probably won't work...it definitely will not fit in the dash...plus you'd need the IHKA with the MAX button which has a different operating software for the MAX pre-programmed setting. Since the e38's IHKA has more redundant controls for the driver/passenger side....plus the e38's blower and FSU is totally different than those found in the e39 & e53...the ZCS coding will probably be different thus create erratic and other control features.

I even wonder if it will work at all. ALL these comments are not based in actual facts (except for the size...e38 IHKA is longer than the e39/e53 IHKA)...but assumptions based on "principles of operation" and BMW build/design architecture.


I'd first run the 11 digit BMW part nbr through one of the part compatibility features on realoem.com or bmwfans.info which could possibly widen the search for a used one if certain e39 model year IHKA units are compatible. But I do wonder still because the latter e39s have a solar sensor...and I'm not sure if the e53 has that added feature...at least, not that I've seen. The same goes with the e38, too. The latter models had a solar sensor that is hidden in the DWA red LED built into the grill on top of the dash...and the wiring harness runs down to the e38's IHKA. The e39's solar sensor sort of sat out on the dash...stinking up from one of the defrost vents in the center...and its wiring harness also runs down to the e39's IHKA. But I've not seen a solar sensor on my 06 X5...so I'm not sure if the HVAC system has a solar sensor.

E39 Solar Sensor (located near center defrost vent)

E38 Solar Sensor (hidden in DWA red LED)