Weird. A/C "Auto" went off on its own
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Senior Member
Joined: Mar 2003
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From: Stamford, CT
2003 C230
Weird. A/C "Auto" went off on its own
I had both "Auto" on and "A/C off" button on. Made a sharp left turn and the "Auto" button light went off and the "A/C off" button was blinking. Have you guys seen this before?
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From: SoCal. Desert
'16 E350, gone: '03 c230k
Hate to say it ... but I had a problem with the 'auto' lite & function turning off all by itself in my '03 c230k while still under factory warranty. They wound up replacing the whole module and everything has been fine since.
By module, I mean the part you see/touch with the knobs/buttons on it. The one they replaced it with looks slightly different than the original (the A/C off button also has 'rest' on it, and I believe a light next to the word 'rest', but I've never seen the light come on, even when I'm using the A/C and it cycles off).
By module, I mean the part you see/touch with the knobs/buttons on it. The one they replaced it with looks slightly different than the original (the A/C off button also has 'rest' on it, and I believe a light next to the word 'rest', but I've never seen the light come on, even when I'm using the A/C and it cycles off).
Thread Starter
Senior Member
Joined: Mar 2003
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From: Stamford, CT
2003 C230
Thanks, my car is sold, getting picked up tomorrow
And it only did this once. Today it was fine. So, maybe it was a fluke. I actually saw the little A/C module with the digital display on it. It's only around $200 or less. At one point I thought about getting it just for the looks. I guess the new owner may have to replace this at some point if it becomes a real issue.
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From: Ashburn, VA
'19 GLC 300, '19 TM3SR+
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Member
Joined: Feb 2006
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From: Southern CA. Orange / Irvine / Long Beach
08 CLS550 Diamond White 09upgrades
it happens
I had this problem for a while now; since under warranty to out of warranty... I complained under warranty; dlr did not do anything because they cannot duplicate the problem...
Now out of Warr. and I just turn on manually ;-)
Now out of Warr. and I just turn on manually ;-)
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From: SF Bay Area, CA
2006 E55 and 2002 E320
Vadim is trying to convert us to E92 3-series people. For those of you thinking of changing to a new car, the new BMW 3-series coupe is very impressive and worthy of your consideration. Believe it or not, I would actually acquire the new BMW E92 over the W204!
Stick around Vadim!
Stick around Vadim!
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Joined: Dec 2008
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From: MD
2007 C230 and 1985 Monte SS
Bringing this back from the dead...
I had this problem intermittantly, and now it is to the point where it happens several times in one hour long commute. I was searching for an HVAC re-sync procedure, and was unable to find it on the forum or in the manual.
It's an '07 C230 sport sedan with the knobs to control the temperature (I believe that I read that there's a digital option).
Luckily, I'm still under warranty, so if a re-sync doesn't exist, or doesn't fix it, I can get it replaced.
I had this problem intermittantly, and now it is to the point where it happens several times in one hour long commute. I was searching for an HVAC re-sync procedure, and was unable to find it on the forum or in the manual.
It's an '07 C230 sport sedan with the knobs to control the temperature (I believe that I read that there's a digital option).
Luckily, I'm still under warranty, so if a re-sync doesn't exist, or doesn't fix it, I can get it replaced.
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From: Toronto, NYC
2002 Mercedes Benz C230 Coupe
Your battery is low. The computer is switching off all major power consumers to save power.
Switch off environmental control, radio, seat/steering heater, unplug everything from the cig lighter socket (all major power consumers) and drive around at a constant speed for a while. this will recharge your batteries.
if that doesn't work you might have to change your battery because its not holding charge too well.
Switch off environmental control, radio, seat/steering heater, unplug everything from the cig lighter socket (all major power consumers) and drive around at a constant speed for a while. this will recharge your batteries.
if that doesn't work you might have to change your battery because its not holding charge too well.
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From: MD
2007 C230 and 1985 Monte SS
If that's the case, its a bad alternator. This happens while driving 70 down the highway. Wouldn't a warnging pop up in the display? This car tells me everything else that could be wrong, I'd imagine a car with no immediately visible voltage meter would have to notify you through the display of a problem.
I'll check it out in dyno mode to see what the voltage reads, but I definately need to get it into the shop so that they can get it fixed and I can make sure of it before another 7500 miles go by and I lose my factory warranty.
I'll check it out in dyno mode to see what the voltage reads, but I definately need to get it into the shop so that they can get it fixed and I can make sure of it before another 7500 miles go by and I lose my factory warranty.
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From: Huntington Beach, Ca.
'17 Jaguar XF
This use to happen to me all the time. Only the driver's side would shut down, and at varying times between instances. I had everything (lower dashes and center stack) out looking for a random clicking noise several times and finally ended up disabling the right defrost stepper motor to stop the noise. The AC hasn't shut down since. I doubt there is a connection between the two but maybe the unplugging and replugging of the AC module did it. I did use a good contact cleaner on the plugs and receptacles while doing the work and I think that did the trick.
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From: Huntington Beach, Ca.
'17 Jaguar XF
And....on board A/Cdiagnostics:
A/C sensor values when holding the EC and REST button for ~10 seconds.
01 In-car temperature sensor.
02 Outside temperature sensor.
03 Heater core temp, left.
04 Heater core temp, right.
05 Evaporator temperature sensor.
06 Engine coolant temperature.
07 Refrigerant pressure in bar (e.g. '4' is 4 bar).
08 Refrigerant temperature.
09 Not used.
10 Heater blower control voltage (normal 08-6.0, meaning .8 to 6 volts).
11 Emissions sensor voltage (to detect atmospheric gases and recirculate interior air).
12 Sun sensor voltage (to shift airflow in car).
20 Control current for auxiliary fan (electric fan on radiator, given in milliamps or mA).
21 Engine speed (x100).
22 Road speed (km/h or mph depending on installation).
23 Battery voltage at terminal 58d (as a percentage of total voltage, e.g. 99.0 = 99%).
24 Battery voltage (e.g. 12.8 = 12.8V).
40 Climate control software version.
41 Climate control hardware version.
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From: MD
2007 C230 and 1985 Monte SS
Thank you very much! I wouldn't imagine that synchronizing the stepper motors is going to fix my particular problem though, would you agree?
I dont believe that I have an EC or REST button, this is the HVAC module that is equipped in my car.
(Disregard the smudges on the glass... this was a dealer photo that I saved from the ad)
I dont believe that I have an EC or REST button, this is the HVAC module that is equipped in my car.
(Disregard the smudges on the glass... this was a dealer photo that I saved from the ad)
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Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
Hopefully! Listen for clicking an popping noises while it's going through the process. You can feel the air changing direction through the vents with our hands. If it makes noises at one vent and doesn't progress normally (takes too long) then you have a problem with that motor. Good luck!
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From: Toronto, NYC
2002 Mercedes Benz C230 Coupe
If that's the case, its a bad alternator. This happens while driving 70 down the highway. Wouldn't a warnging pop up in the display? This car tells me everything else that could be wrong, I'd imagine a car with no immediately visible voltage meter would have to notify you through the display of a problem.
I'll check it out in dyno mode to see what the voltage reads, but I definately need to get it into the shop so that they can get it fixed and I can make sure of it before another 7500 miles go by and I lose my factory warranty.
I'll check it out in dyno mode to see what the voltage reads, but I definately need to get it into the shop so that they can get it fixed and I can make sure of it before another 7500 miles go by and I lose my factory warranty.
I fixed it by driving for a while with all the power consumers off. Since then its worked like a charm.
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2019 G70 6MT & 2022 Ford Maverick XL
On the facelift cars, press and hold front defrost and recirc buttons at the same time.
Then again, if I were under warranty I'd just bring it in. If it is repeatable now it shouldn't be an issue.
Then again, if I were under warranty I'd just bring it in. If it is repeatable now it shouldn't be an issue.
Super Member
Joined: Dec 2008
Posts: 526
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From: MD
2007 C230 and 1985 Monte SS
Just got a call from my SA, and she said that there was a bulletin for the blower motor regulator, and they are replacing it. According to what she said, the symptomes my car has match up to what the bulletin says. I'll report back with the results.
