Air condition on by itself
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Senior Member
Joined: Jul 2003
Posts: 380
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From: So Cal
2003 C230
Air condition on by itself
Sometimes the AC will be on by itself (switch is off). I notice that when I start the car and the engine sound is a little different and I can feel a little breeze. I then switch it to on then off to shut it off.
I don't have a digital AC. It's the dial kind.
Any suggestion?
Thanks.
I don't have a digital AC. It's the dial kind.
Any suggestion?
Thanks.
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2019 G70 6MT & 2022 Ford Maverick XL
I'm not sure, really. I know that some members have a problem with the A/C system shutting off on its own. Maybe it's the same sort of thing, only reversed? I've never read about this before.
Thread Starter
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From: So Cal
2003 C230
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From: Orange County
2005 C Wagon (No snickering please!)
Some cars have a low temperature sensor that runs the AC compressor for five minutes at start up to heat and circulate oil in the system and to remove moisture from the passenger compartment air to prevent the windows from fogging up. You heavy breathers, you.
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Thread Starter
Senior Member
Joined: Jul 2003
Posts: 380
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From: So Cal
2003 C230
I will let it run by itself without turning it off immediately like I used to do.
Thanks.
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From: Saint Augustine, FL
1999 CLK320 (sold), 2007 C230 SS (gone), 2000 Grand Marquis, 2011 CR-Z, stay tuned...
If you have had the AC on, and turn the system off, the AC stays on, just the fans turn off. If you have a window open, or something, it will pull air through the system. Does this sound like it?
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Seriously? I can't imagine that the system is programmed to leave the compressor running when the fan is completely off. Doesn't make sense.
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Drew I don't think that's right. Shutting the system down will shut down the compressor. This can be felt in my car. Now if I simply turn the a/c off but leave everythingelse on the compressor continues to run for several minutes. But turning the system off means the system should be off completely. An open window or roof will create airflow but it shouldn't be conditioned air even though it might feel cool at first.
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From: So Cal
2003 C230
This happens only when I start my car in garage or after work. I can hear the engine running and another sound then I put my hand close to the vent to feel the cold air. This is how it happens the very first time.
It happened a few times already. Now I just turn the ac knob on and off to turn it off.
As Moviela suggested, I will let it run next time. I will see if it shuts down in 5 minutes.
It happened a few times already. Now I just turn the ac knob on and off to turn it off.
As Moviela suggested, I will let it run next time. I will see if it shuts down in 5 minutes.
Last edited by Taiwanese; Mar 11, 2010 at 12:28 PM.
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From: Orange County, CA
2006 C230 SS, 2006 S500, 2008 CLS550 Lorinser
This is just a shot in the dark, but in my 203, when you have the front defroster on, when you turn the defroster off (just the defroster, not the fan speed control) the A/C light will still stay on and you will feel some air coming throught the vents, even if the system is/was off and the Fan Speed Control dial is at "0". And it will stay like that until i turn the air on then back off. Do you ever shut down your car the night before with the defroster on?
And Matt, i dont know the lgoistics of it, but it is bad to stop your compressor dead, which is why it is recommended that you turn your A/C off before you turn your engine off, so my guess would be that when your switch off the A/C the compressor runs for a few minutes to whine down rather than stopping it dead in its tracks.
And Matt, i dont know the lgoistics of it, but it is bad to stop your compressor dead, which is why it is recommended that you turn your A/C off before you turn your engine off, so my guess would be that when your switch off the A/C the compressor runs for a few minutes to whine down rather than stopping it dead in its tracks.
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From: Bay Area, CA
2006 C280
hmm, never heard of that one Taiwanese. I also have a problem with my A/C where when i turn on my front windshield defogger, the A/C button lights up (turns on) after I shut off the defogger. Not sure if this is normal, but good luck.
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From: Orange County, CA
2006 C230 SS, 2006 S500, 2008 CLS550 Lorinser
