Air conditioning problems in high temp
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2009 C300 4Matic
Air conditioning problems in high temp
I have a 2009 C300 4Matic. I am experiencing a problem where in high heat (95-100 degrees F), after my car has been sitting in direct sun, the air conditioning does not work reliably. On many days, it goes from blowing cool air to very hot air, oscillating back and forth.
Last week I actually captured video of this with a digital thermometer, and over the course of 5 minutes it went from 75 to 85, then back down to 72 and then all the way up to 95 degrees, then back to 78 and all the way up to 95 directly out of the vents.
The dealer is struggling to reproduce the problem, as we don't have that many hot days here in Colorado. Has anyone experienced this, or have any ideas what could be causing it? Thanks in advance.
Last week I actually captured video of this with a digital thermometer, and over the course of 5 minutes it went from 75 to 85, then back down to 72 and then all the way up to 95 degrees, then back to 78 and all the way up to 95 directly out of the vents.
The dealer is struggling to reproduce the problem, as we don't have that many hot days here in Colorado. Has anyone experienced this, or have any ideas what could be causing it? Thanks in advance.
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
I have a 2009 C300 4Matic. I am experiencing a problem where in high heat (95-100 degrees F), after my car has been sitting in direct sun, the air conditioning does not work reliably. On many days, it goes from blowing cool air to very hot air, oscillating back and forth.
Last week I actually captured video of this with a digital thermometer, and over the course of 5 minutes it went from 75 to 85, then back down to 72 and then all the way up to 95 degrees, then back to 78 and all the way up to 95 directly out of the vents.
The dealer is struggling to reproduce the problem, as we don't have that many hot days here in Colorado. Has anyone experienced this, or have any ideas what could be causing it? Thanks in advance.
Last week I actually captured video of this with a digital thermometer, and over the course of 5 minutes it went from 75 to 85, then back down to 72 and then all the way up to 95 degrees, then back to 78 and all the way up to 95 directly out of the vents.
The dealer is struggling to reproduce the problem, as we don't have that many hot days here in Colorado. Has anyone experienced this, or have any ideas what could be causing it? Thanks in advance.
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2009 C300 4Matic
These are classic symptoms... you need to have the system checked for low refrigerant. The system will cool for about an hour tops, then the Evap coils will start to freeze up and the system will blow hot air instead. You have a small leak. You need to inject UV dye and a black-light to find it. Replace the faulty part and recharge. End of story. There is a compressor solenoid that shuts down when it detects a low 134a level.
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
Then you need to throw on a set of gauges to see the pressure on both the low and high side. If that's ok, then check to see that the compressor is actually engaging when you turn on the AC. You can tell by the inner pulley rotating as the clutch engages. Have someone turn the system on and off as you observe. If it's not, and you have ok system pressure, then its a bad solenoid on the compressor. If not, they didn't fix the leak properly. Good luck.
Last edited by MBRedux; Jul 27, 2012 at 03:29 PM.
Thread Starter
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Joined: Jul 2012
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2009 C300 4Matic
Then you need to throw on a set of gauges to see the pressure on both the low and high side. If that's ok, then check to see that the compressor is actually engaging when you turn on the AC. You can tell by the inner pulley rotating as the clutch engages. Have someone turn the system on and off as you observe. If it's not, and you have ok system pressure, then its a bad solenoid on the compressor. If not, they didn't fix the leak properly. Good luck.
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SL55, ML500 & Acura TL
Your getting some great advice here. I just wanted to add that pin hole leaks can be a ***** to chase down. A leak may have been identified and repaired, but there could be more. Slapping a set of gages back on the system will tell the story.
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'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Then you need to throw on a set of gauges to see the pressure on both the low and high side. If that's ok, then check to see that the compressor is actually engaging when you turn on the AC. You can tell by the inner pulley rotating as the clutch engages. Have someone turn the system on and off as you observe. If it's not, and you have ok system pressure, then its a bad solenoid on the compressor. If not, they didn't fix the leak properly. Good luck.
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
This is a swashplate compressor. Simply, do you see the pulley on the compressor? Now see the center plate with the three small rings on it? When the compressor is not engaged, that center plate is stationary but the outer pulley is rotating with the engine. When you turn on the AC, that center plate will now turn in unison with the pulley. Have someone turn the system on and off while you observe to see if this is happens. If not, either the solenoid is broken, or the system lost all it refrigerant once again. It sounds like this may be above your comprehension. Unfortunately, you will need to have it looked at by a professional shop.
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From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
The compressor is located usually along the front bottom of the engine, sometime on the left or right at 5 and 7 o'clock. It will have black belt running it and look something like this.
This is a swashplate compressor. Simply, do you see the pulley on the compressor? Now see the center plate with the three small rings on it? When the compressor is not engaged, that center plate is stationary but the outer pulley is rotating with the engine. When you turn on the AC, that center plate will now turn in unison with the pulley. Have someone turn the system on and off while you observe to see if this is happens. If not, either the solenoid is broken, or the system lost all it refrigerant once again. It sounds like this may be above your comprehension. Unfortunately, you will need to have it looked at by a professional shop.
This is a swashplate compressor. Simply, do you see the pulley on the compressor? Now see the center plate with the three small rings on it? When the compressor is not engaged, that center plate is stationary but the outer pulley is rotating with the engine. When you turn on the AC, that center plate will now turn in unison with the pulley. Have someone turn the system on and off while you observe to see if this is happens. If not, either the solenoid is broken, or the system lost all it refrigerant once again. It sounds like this may be above your comprehension. Unfortunately, you will need to have it looked at by a professional shop.
BTW, notice the glossy paint recently polished and sealed (by random orbital, Menzerna Nano-polish and Sealer) as I continue preparing the car for the MB Car Show on 8/12.
Last edited by RLE; Aug 2, 2012 at 12:35 AM. Reason: add photo
