KPatel8483

Hello,

I have about 70000 miles on my 2008 BMW 550i and recently I've noticed the driver side foot well and defrost vents have a lot of hot air coming through. Passenger side vents work as they are suppose to. I have both temp knobs set to coldest temperature settings, iDrive vent setting is set to 4 blue bars. I played around with Auto blower fan vs Manual fan settings, recirculation settings, A/C on and off, and the front windshield defrost button (even then the front windshield only get hot air except for the extreme passenger side vent which gets cold air). After all this it still blows hot hot air. With the A/C on it makes the left center vent slightly cooler but it is still warmer than the right center vent. Outside temperature was around 60 degrees Fahrenheit it feels like it was like blowing hot air from the engine bay. With A/C ON passenger side feels pretty cold but not sure if Freon is running low that would cause this issue because irrespective of A/C ON or OFF the driver side is a lot hotter than passenger side.

Two things did occur prior to this issue:
1. Coolant Expansion Tank had a crack so I had to replace that.
2. I left my radar detector on overnight which is hard wired to a fuse tap and caused an increased discharge battery warning.

Not sure if these two incidents caused something to fail like vent flap motors or heater valves or are just coincidence.

I've checked these two posts here:
https://5series.net/forums/e60-discu...side-c-123505/
https://5series.net/forums/e60-discu...warmup-124848/

Which refer to heater valve issue or hvac flap servo motors.

Is there anything I can check that would help me nail down this issue or a fuse that could be blown preventing driver side from getting the correct air flow that is the same temperature as the passenger side?

Thanks,

KPatel8483

Update on this issue in case anyone else is experiencing this problem. It turned out to be the heater control valve that was stuck in the open position. It would never close regardless of the climate control settings after having it replaced everything is back to normal; cold air from A/C again.

turboawd

that sounds like a hard thing to get access to. lol
congrats on the fix.

tonyb635

I had one of those fail on me once. It was on a really old 528e manny moons ago and driving around with the heat on in the summer was terrible. On that car it as an easy fix, not sure about the E60.

audiophool

If the drawing here is anything to go by, the valve looks like it's mounted to the left frame rail and should be easy to access. RealOEM.com BMW E60N 535xi Water valve/Water hose IHKA High

christian5660

im having a similar issue with my 07 525i I don't get cold air from my normal ac, but I do when I turn max ac on. the shop said my system is working fine and pressures where good. he reffered me to the dealer but said he thinks its the head unit or the actuater door in the dash. all my vents blow the same temp air tho. I wonder if my heater valve has anything to do with it.