It's getting hot in here...

[Sean486]

HVAC system blows 85 degree temp air on all settings. The display numbers will change but it never cools. Vent and Econ also dont see to make it cool off although it does change the vent position. Is it time to look for a new HVAC unit?

[Hocrest]

There is a button sequence to run a diagnostic on the HVAC control unit. Try that?

[Sean486]

Do you think disconnecting the battery for a while might do anything?

[Hocrest]

It won't blow hot air while the battery is disconnected ;-)

[Hocrest]

http://www.subaru-svx.net/forum/showthread.php?t=54000

[svxfiles]

Originally Posted by Hocrest

It won't blow hot air while the battery is disconnected ;-)

Thank you David for being so helpful.

[Sean486]

I feel like it is most likely the control unit and I know from working with computers that reboots do wonders (although I don't expect it will help this time). Anyhow it's a good idea to run the diagnostics. I will try disconnecting the battery too ...nothing to lose.

Good news here is that in the end, it is winter and I still have heat. I can always open the window.

[wdb]

Originally Posted by Sean486

I feel like it is most likely the control unit and I know from working with computers that reboots do wonders (although I don't expect it will help this time). Anyhow it's a good idea to run the diagnostics. I will try disconnecting the battery too ...nothing to lose.

As my non-existent Jewish grandmother from the Bronx always said - "It can't hurt!"

Good news here is that in the end, it is winter and I still have heat. I can always open the window.

My luck ran the other way. I had a heck of a time turning the heat on, and froze to death in the winter. I was usually able to get it back on track by turning the system off altogether and then back on again.

[Sean486]

I get code 13 and 33 faulty mix door motor. I'm a bit confused by that I thought the mix door motor controlled the what vent it blew out of and that is working fine. Or am I wrong and it is referring to rhe motor located on the passenger side?

[svxcess]

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It could be that the air mix door is stuck closed. You can see it if you stick your head under the PASSENGER side of the dash, a little metal bar connected to a motor and a plastic arm at the other end. Try warming up the car then turn on the heat and reach up and jiggle the rod and see if it opens with a little help.


I had a similar problem. While cleaning my interior, I lifted up the passenger floor mat and found a small, long skinny screw on the floor. Looked new. I looked under the dash to see if I could find if it came from there. Turned out that screw fell out of the arm that connects to the door. I operated the system and the arm would move. Replaced the screw, with some Loc-tite and everything worked normally.

Evidentally, the screw unscrewed itself over the years until it fell out. Hope this is all it is.
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[Sean486]

I'll check the motor on the passenger side. I have a couple of those in the garage if I need one.

The car also started stumbling a bit at idle today, so something else to investigate.

[Sean486]

svxcess I followed your advice and shook the metal bar connected to the motor. It must have worked cause now it is does cool off and go into ac mode when I set it to 65. I'm surprised since it didn't seem like anything was moving when I tugged on the metal bars. Anyhow things are good again in SVXland.

[svxcess]

Great news! Did you find any missing screws or areas where it looked like it was binding? At least you know the motor and related electronics are working.

Maybe a little silicone lubrication will keep things from sticking.

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