Which is kinda annoying since its below 24' out.

My heater will work fine and then decide to change over to blowing cold AC. Not fresh air.. but cold AC.

I can either have it set at AUTO, or manually controlling the fan and setting the temp. This will happen at ALL temps. I could set it at 80' and it will still blow AC (while inside the car is close to 30'!).

It will work blowing hot air.. and at some random point switch over to AC instead (to maintain what it thinks is a proper temperature)

So, my assumption is that my temp sensor is off. It can't tell the actual temp in the car.

Where is this sensor located? Is it in the actual controls (lower dash) or somewhere else? I may see if swapping it out fixes it (Im way out of warranty)

06 Cabrio MCS

Thanks for any help or advice!

 

I don't know if the vents are vacuum actuated or electric. My old Cougar would have the light covers close going up a hill since they were vacuum powered.

If they are vacuum, you have to consider a leak. Others will know if it is electric or not.

 

Its definitely not a vacumn problem. A vac wouldn't cause the AC to turn itself on.

Its not that vents are closing.. its that it is actually turning on the AC when it should be blowing heat.

But thanks!

 

The temp sensors are in the a/c control panel unit. You can see them as little slatted circles on both sides of the unit. No idea if they can be replaced or not without getting a new panel. But, under manual mode, what the sensors read should be irrelevant - you can blast heat in the summer with in-car temps soaring, or run a/c in winter with in-car temps below freezing. Thus, I suspect that these temp sensors are not your problem. I am unsure what it could be.

Is the snowflake button lit up? I haven't really figured that one out, but it blows hot and cold when desired with it lit up.

 

THe snowflake has always confused me too.

You are right, on manual, setting it to HIGH (or 80') will also cause it to randomly turn into AC. But.. if there is a temp (ie: 80') it has to be trying to match that AND if the sensor is off it could think that its 200' in my car and thus turning on the AC to compensate.

 

It'a normal in auto for the A/C to come on (to dry out moisture from inside the car) - but it should blow warm.

It would be worth having your battery checked, any auto parts store can load test it right in the car for you.

When my A/C was coming on randomly (even when not using the auto setting) last winter in my truck during a cold snap......... 2 weeks of that and then one of the batteries failed prematurely at less than 3 years old. (2 batteries in a diesel). Got the battery replaced under warranty and the random A/C business quit. Apparantly the low battery was causing electronic gremlins.

 

Wow.. that IS interesting!

I left my GPS on for a few days two weeks ago (in the bitter cold) and my battery was dead when I tried to start it.

I jumped it (via the cig. socket) and have been driving it for weeks since.


BUT.. that IS a strange coincedence.

 

So now the question is, how old is your battery? Your car is an '06, if you're still using the original battery you may be on borrowed time.

....Les