Ford Focus ST Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
1,072 Posts
Discussion Starter · #1 ·
Hey all,
Been a while since I was on here, so forgive me if this is already a topic, but lately I have been getting a weird electronic glitch with me heating and cooling system.
So Ill be driving along, No A/C or heat and then just all of the sudden my heat will blast on Hi and full fan and typically on jut my feet. It does not happen often, once per week, maybe.
I have not said anything to the dealer yet since its random and I cannot repeat it for them.

Just wondering if anyone else has had this? or knows whats going on?

Im starting to think I have an exposed connection or a short somewhere but Id rather not tear my dash apart to search for it if Im not sure its there.
 

·
Registered
Joined
·
361 Posts
One time I got in my car and the AC was on full blast but no air was coming out of any of the vents! :shocked: I turned the car off, then re-started it and it worked fine after that, and it's never done it since.
 

·
Registered
Joined
·
41 Posts
Hey, I thought I was the only one...

Yup, this happens in my '16 ST2 as well. Not MFT-related. I let it slide since it only happens occasionally and I've been distracted by more pressing matter at the dealership, like misfires.
 

·
Registered
Joined
·
210 Posts
if the automatic a/c "looses" the link to the outside temp sensor it defaults to thinking it is below freezing outside and turns the heat on full blast. Learned this when a bird strike ripped the pass' side mirror off - this is where the outside temp sensor is ..... with the mirror gone, every time I started the car the heat came on full blast for about 3 minutes until the system realized the temp INSIDE the car was over 90 ..... yep, I live in Florida and this was summertime!

Could be a loose connection at the mirror/door. The mirror connects to the wiring harness with a multi-pin plug just inside the door.

btw ... my experience with Ford service technicians on this problem was not good. When the heat on issue began with the mirror being gone, I was not sure they were related and asked if the outside temp sensor was in the missing mirror (I could have had damage behind the grill too). "No, absolutely not" was what I got from the 'trusted a/c guy' at a big Ford dealership. But I waited to let them work on it until AFTER I got the new mirror. Lo and behold with the new mirror (all wires properly connected) the climate system went back to 100% normal function. In the 'tween time, I'd learned from this site that the outside temp sensor IS in the pass' side mirror. (looks like a lil black bump on the underside of the mirror ... on a 14 anyway.)
 
  • Like
Reactions: hmc2261
1 - 6 of 6 Posts
Top