Heater control valve goes hot and cold, nothing in between

Post in this forum for topics relating to the interior.

Moderators: GRNSHRK, ron, bfons

Post Reply
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Heater control valve goes hot and cold, nothing in between

Post by ronnieg »

It appears that when I move the heater temp control off of the "off/cool" position, I only get completely hot air from the heater. It used to modulate the temperature correctly, so something went haywire.

Any clues for where to look?
Happier in a 635
User avatar
Ralph in Socal
Platinum Member
Platinum Member
Posts: 2745
Joined: Tue Apr 14, 2009 3:32 am
Location: High Desert of SoCal

Re: Heater control valve goes hot and cold, nothing in between

Post by Ralph in Socal »

The Interior Air Temperature Sensor in the Drivers side kick panel. It's the weird looking one with a round hole on the front and a vacuum hose attached to it on the back. Make sure it's connected properly on both the electric and vacuum lines.

Also known to go bad and, of course, outrageously expensive new.

Hope someone else can provide troubleshooting steps since I can't help with that.

Ralph
There is a very fine line between "Hobby" and Mental Illness.

85 635csi Zinno Auto
84 528i Euro
83 635 Euro Arktik
81 528i Kastanien 5-speed
88 528e Bronzit (Granpa Car)
86 535i Auto (For Sale)
81 633 csi (retired)
ronnieg
Posts: 106
Joined: Sat Jan 12, 2013 4:07 am
Location: Denton, TX

Re: Heater control valve goes hot and cold, nothing in between

Post by ronnieg »

Easy fix, and I feel like a dope....

Apparently when locking down the hood lever inside the car (with my foot), I believe my shoe or toe got caught on the connector for the temp sensor. Was dangling freely.

All better now. Not to self.....close and lock the hood down more thoughtfully!
Happier in a 635
Post Reply