Does the Air Conditioning Compressor Disc always turn on a 2007 ML350? No cold air.
Thread Starter
Newbie
Joined: Mar 2017
Posts: 2
Likes: 0
2007 ML350
Does the Air Conditioning Compressor Disc always turn on a 2007 ML350? No cold air.
I'm not getting cold air with the AC. The disc associated with the AC pully on the poly belt, the lower right one looking from the front of the engine, is always turning with the engine running, whether the AC is turned on or not. I am used to vehicles where that only turns when the AC is on. Does anyone know if it always turns on an 07 ML350?
I tried to add coolant to the lower pressure side filling attachment. But the Mercedes receptacle is so deep I am not sure the filling attachment I have is reaching down far enough to open up the valve to allow coolant into the car's AC system. Does anyone know if a special attachment is necessary for filling a Mercedes AC system?
The coolant level must be really low because when I use a small screwdriver to depress the low pressure valve inlet only a tiny bit comes out, like a tire with 3 psi in it. With the engine running, when I turn the AC on with my friend's head under the hood right over the engine compartment there is no audible change in noise, no clicks, no nothing.
Anyone know what I can do to get my AC going?
I tried to add coolant to the lower pressure side filling attachment. But the Mercedes receptacle is so deep I am not sure the filling attachment I have is reaching down far enough to open up the valve to allow coolant into the car's AC system. Does anyone know if a special attachment is necessary for filling a Mercedes AC system?
The coolant level must be really low because when I use a small screwdriver to depress the low pressure valve inlet only a tiny bit comes out, like a tire with 3 psi in it. With the engine running, when I turn the AC on with my friend's head under the hood right over the engine compartment there is no audible change in noise, no clicks, no nothing.
Anyone know what I can do to get my AC going?
Junior Member
Joined: Jul 2012
Posts: 33
Likes: 4
From: California
2015 C300, 2014 GLK 250 Bluetec
no special attachment needed that I ever had to use. Not sure what could be the problem without more info though. It may not necessarily be low refregerant. It blows air, just not cold, correct? does the low side line get cold to the touch? If you are able to get gauges on it and pull some codes we might be able to see whats going on?
MBWorld Fanatic!
Joined: Jan 2014
Posts: 3,966
Likes: 1,315
From: Republic of Texas
'99 and '05 E55 AMG
Start learning about "swash plate air conditioning compressors".
Here's one for introductory info:
https://axleaddict.com/auto-repair/V...nt-Compressors
Here's one for introductory info:
https://axleaddict.com/auto-repair/V...nt-Compressors
Last edited by bbirdwell; Mar 17, 2017 at 10:29 PM.
Member
Joined: Nov 2014
Posts: 245
Likes: 7
2008 gl320cdi
Mine has been doing same for over a year. Although it is happening more consistently
mechanic recently looked at it and told me it is a valve sticking. I think external. But said whole compressor would need to be changed. I am waiting to see. I would like to recharge and may try first to see if fixes.
mechanic recently looked at it and told me it is a valve sticking. I think external. But said whole compressor would need to be changed. I am waiting to see. I would like to recharge and may try first to see if fixes.
Super Member
Joined: Jan 2013
Posts: 636
Likes: 29
From: MN, USA
C43 5.4, ML320CDI, Fords
It does not have an on and off clutch. It is a variable compressor and is controlled within the compressor, you won't hear a click or any noises.
I'd take it to your dealer for a proper diagnosis.
I'd take it to your dealer for a proper diagnosis.
