Why is my heat going to "Auto" by itself?!?!

[Egon Spengler]

I was driving down the road on Friday and all of a sudden my heat turns on and it says "Auto". I didn't touch a thing! So I shut it off and about 5 minutes later it does it again! Also, I hear a creaking sound come from the passenger side floor when I turn my car off and on even with the heat off. I am guessing these are two separate issues. What is causing these issues to happen? Anyone ever have these problems?

Thanks everyone!:beer:

[4play]

Maybe run the code diagnostic, forget how, I'm sure someone will chime in.

[DOOM]

Egon has ghosts!!! :eek:

:lol:

[MM2004]

Egon has ghosts!!! :eek:

:lol:

I know who he can call.

:D

Mike.

[Egon Spengler]

Egon has ghosts!!! :eek:

:lol:


I know who he can call.

:D

Mike.
I aint afraid of them though! Just looking to extricate them from my possessed vehicle! haha.

There is no Marauder... only Zuul...

[SC Cheesehead]

I aint afraid of them though! Just looking to extricate them from my possessed vehicle! haha.

There is no Marauder... only Zuul...

Dr. Peter Venkman (http://www.imdb.com/name/nm0000195/): Generally you don't see that kind of behavior in a major appliance.

[Egon Spengler]

Nobody has an answer for this besides Ghostbuster quotes?

(tickling first two ivories of piano) "They hate this. I like to toy with them. That right boys! It's Doctor VENKMAN!"

"Look at all the junk food. You actually eat this stuff?"

[Blackened300a]

Nobody has an answer for this besides Ghostbuster quotes?

The creaking you hear is the blend door working the vents. You should also hear a vacuum sound as well when it closes. If its working that eliminates the blend doors and a vacuum issue. Im going to say its in the head unit. Im vaugely remembering something similar happening before my head unit was replaced under warranty.

[Egon Spengler]

The creaking you hear is the blend door working the vents. You should also hear a vacuum sound as well when it closes. If its working that eliminates the blend doors and a vacuum issue. Im going to say its in the head unit. Im vaugely remembering something similar happening before my head unit was replaced under warranty.
It hasn't done it again since that one time. The blend door is functioning just fine that God! I may look into a new head unit. What cars share this head unit? GM/CV? Any other vehicles with the built in exterior temp reading?

[4play]

I have put a head unit in from a 2001 gm it worked fine except I had no steering wheel controls, did u try pulling a code then resetting the unit, once mine went screwy I just did a reset and it's been 100% for a year now.

[Egon Spengler]

I have put a head unit in from a 2001 gm it worked fine except I had no steering wheel controls, did u try pulling a code then resetting the unit, once mine went screwy I just did a reset and it's been 100% for a year now.
I have NO idea how to do any of that! haha

[Blackened300a]

I have NO idea how to do any of that! haha

The HVAC self test. Unfortunatly the search function sucks and I don't remember it off hand. It will cycle the doors and reset the head unit. Someone will chime it, I think its FLOOR, AUTO, then press OFF.

[Egon Spengler]

The HVAC self test. Unfortunatly the search function sucks and I don't remember it off hand. It will cycle the doors and reset the head unit. Someone will chime it, I think its FLOOR, AUTO, then press OFF.
Thanks. Hopefully someone will chime in. If not, I will try that anyways.

[MrBluGruv]

I think I'm gonna try this myself, my A/C stopped blowing hot RIGHT in time for winter.

Hilarious part is when it's set to 90 degrees, it's never blown colder since I've had it...

[Blackened300a]

I think I'm gonna try this myself, my A/C stopped blowing hot RIGHT in time for winter.

Hilarious part is when it's set to 90 degrees, it's never blown colder since I've had it...

My crown vic would blow 90 degrees just as spring rolled around and I was starting to use the A/C. I did the self test and it worked all the through the summer. If it caused a issue again, I just did the self test and it worked again.

Ill venture to find the self test.

[Blackened300a]

OK Found it.... Press FLOOR and OFF and the same time, then press AUTO within 2 seconds. The display will start going in a circle, then flash a number code. If no code then everything is fine and it will just reset the head unit.

[Egon Spengler]

OK Found it.... Press FLOOR and OFF and the same time, then press AUTO within 2 seconds. The display will start going in a circle, then flash a number code. If no code then everything is fine and it will just reset the head unit.
Thanks buddy! Will go do this on my lunch!

[MrBluGruv]

OK Found it.... Press FLOOR and OFF and the same time, then press AUTO within 2 seconds. The display will start going in a circle, then flash a number code. If no code then everything is fine and it will just reset the head unit.

You sir, are da man. :up:

[Egon Spengler]

You sir, are da man. :up:
Very much so!

[Blackened300a]

Glad a Google search can make me look like a hero. :D

[Egon Spengler]

Glad a Google search can make me look like a hero. :D
Google search seems like a lot better way to find things on this ding dang fangled site.

[Egon Spengler]

Ok, so I went out on my lunch and did the test. When it was done EVERYTHING on the display lit up. I am guess that meant it is done doing what it had to? I had to shut the car off and turn it back on again for the screen to blank out. I didn't have any numbers show up, so I am guessing there were no codes thrown?

[Blackened300a]

Ok, so I went out on my lunch and did the test. When it was done EVERYTHING on the display lit up. I am guess that meant it is done doing what it had to? I had to shut the car off and turn it back on again for the screen to blank out. I didn't have any numbers show up, so I am guessing there were no codes thrown?

If everything lit up then no code was present. Just push hot or cold and it will go back to the temp.

[Egon Spengler]

If everything lit up then no code was present. Just push hot or cold and it will go back to the temp.
10-4! Thanks for the help yet again! haha

[Egon Spengler]

If everything lit up then no code was present. Just push hot or cold and it will go back to the temp.
COP's worked great buddy! Thanks again for them!

[Blackened300a]

COP's worked great buddy! Thanks again for them!

I was just about to ask you that. They cured your stumble at idle?

[MrBluGruv]

Wanted to chime in again,

I ran the test this afternoon and it came back with code 024, which upon investigation I found means a problem with the temperature blend door during calibration.

Do you think this problem is actually in the blend door, or is the the o-rings not holding vacuum any more therefore not being able to adjust it? Forgive me if I'm completely wrong about how this works.

[Blackened300a]

Wanted to chime in again,

I ran the test this afternoon and it came back with code 024, which upon investigation I found means a problem with the temperature blend door during calibration.

Do you think this problem is actually in the blend door, or is the the o-rings not holding vacuum any more therefore not being able to adjust it? Forgive me if I'm completely wrong about how this works.

After you ran the self-test, did everything start working again? The O rings are for the defrost/vent/floor selectors. They work on vacuum. You wouldn't be able to select how to direct the air if that was the problem. Try the self test a few times and going up and down with the temp. That can sometimes free it up.

[MrBluGruv]

After you ran the self-test, did everything start working again? The O rings are for the defrost/vent/floor selectors. They work on vacuum. You wouldn't be able to select how to direct the air if that was the problem. Try the self test a few times and going up and down with the temp. That can sometimes free it up.

The operational capacity stayed the same after the test, nothing got fixed by it. :(

I've putzed around a few times trying to get the temp to change, but it hadn't worked yet. I will try a more serious rigorous routine tomorrow morning with it. Believe it or not, it's actually starting to get a little chilly down here in Texas whenever it's dark. :P

And thanks for the explanation of the o rings, the placement selection isn't a problem yet cause it'll rotate between all supply points no problem, so I'm guessing that problem hasn't manifested yet for me. *crosses fingers*

[Got_1]

Wanted to chime in again,

I ran the test this afternoon and it came back with code 024, which upon investigation I found means a problem with the temperature blend door during calibration.

Do you think this problem is actually in the blend door, or is the the o-rings not holding vacuum any more therefore not being able to adjust it? Forgive me if I'm completely wrong about how this works.

the temp is controlled electronically using an actuator at the temperature blend door

[MrBluGruv]

OK, time for good news bad news about my heater...

Good news is, I managed to get the A/C to blow hot air again this morning after cycling through the temperature extremes a few times then running the EATC diagnostic again.

Bad news is, that dreaded ticking/clacking noise is now present when you try to change temperature (kind of a clacking noise about every second for about 15 seconds.)


I'm leaving it at 90 degrees for now and just switching it off when I don't need hot air, just in case it decided to get stuck on cold again. Interestingly enough, I pretty much completely confirmed that running heat is what causes my subwoofer to stop working correctly and get electrical hum, which kind of leads me to believe maybe the install of the radio got wiring in the way of or gummed up in or around the blend door area.


Thoughts?

[CBT]

I have NO idea how to do any of that! haha

That's what she said.

[Egon Spengler]

That's what she said.
Eff youuuuu

[Blackened300a]

OK, time for good news bad news about my heater...

Good news is, I managed to get the A/C to blow hot air again this morning after cycling through the temperature extremes a few times then running the EATC diagnostic again.

Bad news is, that dreaded ticking/clacking noise is now present when you try to change temperature (kind of a clacking noise about every second for about 15 seconds.)

Its a plastic gear that works with a worm gear on a electric motor. Chances are the plastic gears are stripped and your hearing it jump the teeth.
http://www.carcomplaints.com/media/complaints/images/c66777e0-ca36-102d-8f1f-678b82e8086b.jpg

[MrBluGruv]

Its a plastic gear that works with a worm gear on a electric motor. Chances are the plastic gears are stripped and your hearing it jump the teeth.
http://www.carcomplaints.com/media/complaints/images/c66777e0-ca36-102d-8f1f-678b82e8086b.jpg


Yeh, oddly enough this is the third car in a row in my family to have this exact problem: my '02 Galant got it right under 100K, my mother's 2008 Sable got it (not happy about that, it's not high miles at all), and now my MM has it almost right at 109K.