2008 528i LCI

Out of nowhere, my car will no longer blow heat. No matter how high I set every temp even the little red and blue bars, it will only blow cold air. I use the Carly for BMW app so I was able to diagnose everything just still not sure!

I isolated the parameters for the water pump and figured that it had the proper voltage, etc., leading me to believe that the problem is not the water pump.

However, I did get fault codes in the following manner. My gut leads me to believe that it may be the rain/light/solar sensor (part# 61359201989) is acting up. The only thing that is throwing me for a loop is that the light and rain portion of the sensor still provides the correct information to the ECU to allow the headlights to still turn on and the wipers to wipe. I read that the solar portion of the senor tell the IHKA when to blow heat or cold.

Light/Rain Control:
Rain/light sensor / Regen-Lichtsensor RLS
ECU OK, no Fault Code
Light / Licht
Fault: sorry, unknown fault
Code: A8C4
Heating / AC:
Air conditioning / Klimaanlage
Fault: Monitor sun sensor supply
Code: 9C6D
Fault: Monitor Fondpotiversorgung
Code: 9C6E
Fault: Error fogging sensor - K-LIN 3 RLS
Code: 9C55


I have no idea if I'm heading in the right direction or not. Hopefully some peeps here can help!!!

 

Well, fixed it. It was the light/rain/solar sensor. Heat blows fine again. Got the new piece off of eBay for $36 used.

 

Great!

 

I stand corrected. It worked for about 5 minutes and stopped again...

Thoughts?