Air Condition works then doesnt then does?
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
Air Condition works then doesnt then does?
About a week ago I got in the car and it was blowing hot, I went in to a store and came back out and it worked fine. A good 5 days have passed and it has been working fine.
Today it was blowing hot again, I drove about 35 miles and it never worked, I shut it off and back on by the a/c button 5 or 6 times and no dice. Got out of car to get gas but it still didn't work after starting car back up like it did the week before. Drove another 40 miles or so with it not working and again hitting a/c button to off and on but no help. Went in to a store and came back out and it is blowing cold again.
It doesn't make sense to me to be a low Freon problem so I am thinking some kind of switch that is intermittently working? I am not an a/c guru but does this sound like an accurate problem? Trying to search on my phone but not finding what I need (same problem).
I looked up air conditioning cutoff switch or something like that on advance auto parts website, no clue where this switch is located or if this is the problem, so what do you guys think?
Today it was blowing hot again, I drove about 35 miles and it never worked, I shut it off and back on by the a/c button 5 or 6 times and no dice. Got out of car to get gas but it still didn't work after starting car back up like it did the week before. Drove another 40 miles or so with it not working and again hitting a/c button to off and on but no help. Went in to a store and came back out and it is blowing cold again.
It doesn't make sense to me to be a low Freon problem so I am thinking some kind of switch that is intermittently working? I am not an a/c guru but does this sound like an accurate problem? Trying to search on my phone but not finding what I need (same problem).
I looked up air conditioning cutoff switch or something like that on advance auto parts website, no clue where this switch is located or if this is the problem, so what do you guys think?
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From: Orange County, CA.
one car at a time
Have you checked the pressure of the system ? It is relatively easy and if the AC is low it could be causing the compressor to cut off. I tested my system last year (it was not really cold) and it was low on Freon.
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
I am traveling, haven't done any testing
But like I said, it has been working for a week perfect after the one mishap, that is why it just doesn't seem like Freon being low. Guess you never know but with the way it has acted up once a week ago then today and now perfect again at the moment it seems like something else.
I think I remember reading about a way to go in to controls of a/c in the car for a readout of how many bar of freon pressure or something like that. I will check on it once at my computer computer to see if I can look up that way just to be sure of the amount being correct.
But like I said, it has been working for a week perfect after the one mishap, that is why it just doesn't seem like Freon being low. Guess you never know but with the way it has acted up once a week ago then today and now perfect again at the moment it seems like something else.
I think I remember reading about a way to go in to controls of a/c in the car for a readout of how many bar of freon pressure or something like that. I will check on it once at my computer computer to see if I can look up that way just to be sure of the amount being correct.
Last edited by urbamworm; Apr 14, 2013 at 04:44 PM.
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
David, dose your car have a rest button on the A/C control head?
If so you can pull up the diagnostics for the Climate control system.
If so you can pull up the diagnostics for the Climate control system.
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
Hey Bob, will make a thread when I get home about last night but snagged Elliot's alternator today and it did the trick.
My My car is an 05 and I don't see a button like that. Assuming it is where there is a blank button to the left of the lower fan speed button?
My My car is an 05 and I don't see a button like that. Assuming it is where there is a blank button to the left of the lower fan speed button?
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MBWorld Fanatic!
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From: Caribbean/Florida/Colorado
E-ZGO 53hp., 1999 E 430 sport, 2004 E 55, 2008 Tahoe LTZ on 24"s
Ya I dont remember the trick for the newer cars that dont have the rest button, but there is a way to do it and also get fault codes in the AC too.
here is a little more info,
https://mbworld.org/forums/mercedes-...diag-mode.html
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I use to have this prob in my C32 all the time until i got on the highway and it would finally turn on.
One day i read where someone turned their heater on full blast for a few minutes
I tried this and it did the trick. My AC came on full blast.
One day i read where someone turned their heater on full blast for a few minutes
I tried this and it did the trick. My AC came on full blast.
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From: Pensacola, FL
2003 E55 AMG
Mine did this...it is a pain in the *** to fix. There is a heater control valve located under the hood cowl where the wiper motor and arms attach. I had to change mine out a few months ago. if you have huge hands be prepared to curse a lot and have battle scars. The part is relatively inexpensive, but it fixed me right up. Do all of your vents blow cold or just a few of them? Mine was intermittent like yours, I could have cold air in th eback seats but Hades hot in the front or just all hot. it was crazy. let me search a bit and see where the post is...its in here somewhere.
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From: Pensacola, FL
2003 E55 AMG
Here ya go bro...this may or not be the culprit...if it is...here's the write-up 
https://mbworld.org/forums/e-class-w211/250487-diy-installing-new-changeover-heater-control-valve.html
https://mbworld.org/forums/e-class-w211/250487-diy-installing-new-changeover-heater-control-valve.html
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
Cool, I will check in to it. Got in the car this morning and it wasn't working again. I hit the "off" button then back on and it started working. Hadn't tried that yet when it wasn't working before, I was just hitting the "a/c" button and that didn't help.
It must be that dang valve. I have small hands so I guess that will help out. I haven't noticed different vents blowing different temps though, it was just hot.
Today it has done it twice more but by simply hitting off then off again to turn it back on it would start blowing cold.
NEED a/c right now, it is hot as a **** in south Florida.
It must be that dang valve. I have small hands so I guess that will help out. I haven't noticed different vents blowing different temps though, it was just hot.
Today it has done it twice more but by simply hitting off then off again to turn it back on it would start blowing cold.
NEED a/c right now, it is hot as a **** in south Florida.
Last edited by urbamworm; Apr 15, 2013 at 02:10 PM.
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E63s s213 2019 ,SOLD E63 Weistec, E55, C36
i think pimpjuice has solved this for you, i had the same issue on mine, heater exchange control motor, some still call it the duovalve even tho its not that but performs the same function.
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http://www.mercedestechstore.com/pdf...%208-30-02.pdf
I'll look around for the procedure to get in to the On Board Diagnostics. You can guess all day and throw big $$$$ at it and still never find the on /off problem.
There are 2 diag systems, one gives all the sensor values and the other gives fault codes.
You don't need star or a dealer to do this, it is so easy and finds the problem quick.
I'll look around for the procedure to get in to the On Board Diagnostics. You can guess all day and throw big $$$$ at it and still never find the on /off problem.
There are 2 diag systems, one gives all the sensor values and the other gives fault codes.
You don't need star or a dealer to do this, it is so easy and finds the problem quick.
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From: Pensacola, FL
2003 E55 AMG
Do a simple test of seeing if the different vents are all blowing hot air. If some are freezing cold and some are hot, 95% chance it the control valve. If they are ALL hot then that percentage drops considerably
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From: Michigan, USA
2000 E55 AMG
There's also a temperature sensor on the evaporator. Sometimes these things will freeze up and send the wrong signal to the computer. Other times the resistor itself fries and sends an irrational value to the computer and it thinks it's hotter or colder than it really is and hence your temperature output may be all over the place.
A quick easy test to see if your compressor is working properly, turn on the windshield defogger. This turns the A/C system on also. Locate the A/C compressor, on the W210's it's on the drivers side towards the bottom. If the compressor is locked and turning then it's on. If it clicks on then off then on then off, it's low on refrigerant (it's NOT Freon).
A quick easy test to see if your compressor is working properly, turn on the windshield defogger. This turns the A/C system on also. Locate the A/C compressor, on the W210's it's on the drivers side towards the bottom. If the compressor is locked and turning then it's on. If it clicks on then off then on then off, it's low on refrigerant (it's NOT Freon).
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This place is a joke.
There's also a temperature sensor on the evaporator. Sometimes these things will freeze up and send the wrong signal to the computer. Other times the resistor itself fries and sends an irrational value to the computer and it thinks it's hotter or colder than it really is and hence your temperature output may be all over the place.
A quick easy test to see if your compressor is working properly, turn on the windshield defogger. This turns the A/C system on also. Locate the A/C compressor, on the W210's it's on the drivers side towards the bottom. If the compressor is locked and turning then it's on. If it clicks on then off then on then off, it's low on refrigerant (it's NOT Freon).
A quick easy test to see if your compressor is working properly, turn on the windshield defogger. This turns the A/C system on also. Locate the A/C compressor, on the W210's it's on the drivers side towards the bottom. If the compressor is locked and turning then it's on. If it clicks on then off then on then off, it's low on refrigerant (it's NOT Freon).
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From: Az
2005 e55 amg, 2003 c32 amg, 1998 acura integra gsr k swap, 2000 honda s2000, 2008 honda cbr 1000rr
I've been having issues with my rear vents blowing hot! the fronts work fine, but the rears blow hot, then I would put the rear temp up, then back down to low, then it would work sometimes. Im in AZ and this **** sucks bc the back of you just gets hot even though the front blows cold. Is there a proper name or pic for that valve under the wiper area that should be replaced?
