C43 Condenser Fans operation ?
Thread Starter
Newbie
Joined: Dec 2007
Posts: 12
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C43 AMG
C43 Condenser Fans operation ?
Hi
A quick question for a C43 owner
The two electric fans behind the front hood/bonnet grill are I believe for cooling the AC condenser.
Do they both start up automatically when the Air Con is turned on, or does just one fan start up, or is it pressure/temperature dependent and they will both stay off until needed?
I have done the usual Google search with mixed results
At present with my car none of the condenser fans start when selecting the AC.
My car needs a re-gas and I just wanted to double check the fan operation in-case there were other issues.....
many thanks...
A quick question for a C43 owner
The two electric fans behind the front hood/bonnet grill are I believe for cooling the AC condenser.
Do they both start up automatically when the Air Con is turned on, or does just one fan start up, or is it pressure/temperature dependent and they will both stay off until needed?
I have done the usual Google search with mixed results
At present with my car none of the condenser fans start when selecting the AC.
My car needs a re-gas and I just wanted to double check the fan operation in-case there were other issues.....
many thanks...
Thread Starter
Newbie
Joined: Dec 2007
Posts: 12
Likes: 1
C43 AMG
You could be right, that's the problem there seems to be several answers coming out of Google. Probably will give a dealership a call....
They must know, but will they help without quoting the standard reply, "bring the car in and we will run a diagnostic check for you" ...hmm
They must know, but will they help without quoting the standard reply, "bring the car in and we will run a diagnostic check for you" ...hmm
MBWorld Fanatic!
Joined: Jan 2007
Posts: 1,152
Likes: 29
From: Sydney, Australia
190D 2.5 (x2), 190E 2.6, W202 C240,W202 C43 (C55), W210 E55, W212 E250CDI
Both fans come on together. They can be actuated by eiher the the engine control unit due to temp (I think from about 105C) or the A/C control unit. Most of the time the fans will be on due to the A/C rather than engine temp.
Fans come on once A/C pressure above 15bar and ramp up as the pressure/temps increase. anything under 15bar or 10%C engine temp they should be off.
A/C fans running at full speed all the time is a good indication of a engine temp or a/c temp sensor fault (fans default to full speed) or if the A/C perforamce is poor it indicates air in the system (high pressure but low condensor temps).
Fans almost never coming on is most likely low A/C gas.
Fans come on once A/C pressure above 15bar and ramp up as the pressure/temps increase. anything under 15bar or 10%C engine temp they should be off.
A/C fans running at full speed all the time is a good indication of a engine temp or a/c temp sensor fault (fans default to full speed) or if the A/C perforamce is poor it indicates air in the system (high pressure but low condensor temps).
Fans almost never coming on is most likely low A/C gas.
Last edited by Ausmbtech; Jan 12, 2012 at 11:47 PM.
Thread Starter
Newbie
Joined: Dec 2007
Posts: 12
Likes: 1
C43 AMG
Both fans come on together. They can be actuated by eiher the the engine control unit due to temp (I think from about 105C) or the A/C control unit. Most of the time the fans will be on due to the A/C rather than engine temp.
Fans come on once A/C pressure above 15bar and ramp up as the pressure/temps increase. anything under 15bar or 10%C engine temp they should be off.
A/C fans running at full speed all the time is a good indication of a engine temp or a/c temp sensor fault (fans default to full speed) or if the A/C perforamce is poor it indicates air in the system (high pressure but low condensor temps).
Fans almost never coming on is most likely low A/C gas.
Fans come on once A/C pressure above 15bar and ramp up as the pressure/temps increase. anything under 15bar or 10%C engine temp they should be off.
A/C fans running at full speed all the time is a good indication of a engine temp or a/c temp sensor fault (fans default to full speed) or if the A/C perforamce is poor it indicates air in the system (high pressure but low condensor temps).
Fans almost never coming on is most likely low A/C gas.
Excellent info thanks for the update
Junior Member
Joined: Jun 2012
Posts: 37
Likes: 2
From: Coeur d'Alene, Idaho
1998 C43 AMG
I have a 98 C43 AMG and repair shop determined the cooling fan module (that controls the 2 small ones) is faulty. They want 100's of dollars just for the module. Does anyone know where I can get this module online? Air conditioning gas is full, it blows cool for just a couple minutes then air turns warm. Apparently something is getting too hot that depends on these 2 fans working.
MBWorld Fanatic!
Joined: Oct 2013
Posts: 1,649
Likes: 46
From: New Jersey
1999 AMG C43
plenty of places to source it. i like https://www.mbdirectparts.com/ but there are plenty of other good places. if fcp euro happens to carry it they offer lifetime guarantee
