Hey guys,

I recently got ahold of a 2004 e60 and have a question on the heating system. My issue is that when selected to maximum heat on the control panel and in the idrive, I'm only getting about 70% heat output out of the center vents. If I select defrost on the control panel, the defrost blasts hot air.

I have INPA and tried some tests. It seems like everything is working except the "lamination flap" (this is what INPA calls it, but I think it's the cold air flap?) stays at 30% when the idrive is selected to max hot. If I manually select 0% in INPA, the flap moves and then I finally get max heat out of the center vents. When I move the idrive setting to the cold position, it reaches 100% before I reach max cold. It's almost like it's not set properly.

Is there a way to reset this flap? Is there something else driving this flap to the cooler position when selected max hot?

Things to note, i am getting and AUC sensor fault and the condensation sensor on the windshield looks like it was removed by the previous owner. Could these faults cause my issue?

 

Broken or missing condensation sensor will cause some odd behaviors. The system may think the windows are fogging and give bias to cold air (remove moisture,) to compensate. Really should get that fixed before trying anything else.

 

I'm with Greggo. Fix AUC and condensation sensor if all the hoses are hot once vehicle is at operating temp. Don't know if your vehicle has an aux pump but I'd check the hoses on there also.

 

Thanks for the replies guys.

I did not necessarily fix the issue but masked it (for the time being) by removing the vent temperature sensor (located by drivers center vent) and installing a resistor to make the system think the air coming out the vents is cooler than it actually is. I was then able to get the vents to move to the warmer positions. The system now blasts hot air during our -30 degree Celsius weather. The issues is, once summer comes, I'll probably have to remove the resistor or else it might not go full cold, not sure yet. I'll probably see if there is a doner car to get parts during the spring.

 

I would not recommend a used condensation sensor. Easily damaged removing it.

Happens all the time when the windshield is replaced. Unless it is a BMW dealer, the glass shops do not know how to deal with the RLS or condensation sensors.