[cals]

Hi
The fan / heater control is acting up; I set the fan and it randomly slows down, stops, and restarts after a few minutes. The process repeats constantly with no apparent pattern or underlying reason. The system is NOT in Auto and have been checking the battery as well (voltage while running is 14.1 measured at the lighter)
I have the two zone control with individual driver/passenger seating, heated seats. I tried different settings to see if there is a reason but no impact, the behaviour persists. Any ideas/ suggestions?
Thx

535 ix 2011

[Qsilver7]

Originally Posted by cals

Hi
The fan / heater control is acting up; I set the fan and it randomly slows down, stops, and restarts after a few minutes. The process repeats constantly with no apparent pattern or underlying reason. The system is NOT in Auto and have been checking the battery as well (voltage while running is 14.1 measured at the lighter)

535 ix 2011

Interesting that this sounds like an issue the e39/e46/e53 BMWs used to have when their FSU/FSR (final stage unit/final stage resistor) flaked out.

A google search using "BMW FSR/FSU" should turn up many of those threads...perhaps the F10 is starting to have some of the same issues in regards to this issue.

EDIT: looks like the f10 uses a "blower output stage"...here's a link to the TIS that explains it's function...and it appears to set a diagnostic fault if it starts to fail...so if you have software/hardware...you should be able to retrieve data to see if it may be the culprit: https://www.newtis.info/tisv2/a/en/f...-stage/XRx1kv3

{#4 is the blower output stage...pic taken from link above}



{#2 in the pic below from the part database diagram gives another perspective}
http://bmwfans.info/parts-catalog/F1...ounting_parts/

[cals]

Indeed, I used to have an e39 (2001 Sport Manual - great memories !) and I had that issue so seems more than a decade later (!) could be the same one again.....will check if I can get a code out.