AC issue
Thread Starter
Member
Joined: Nov 2011
Posts: 181
Likes: 4
S600
AC issue
Well I have the car back from getting the EIS replaced by the dealer ($1200 after a 15% discount since they kept the car for over a month to diagnose and fix the problem). They wanted another $1400 to replace the radiator fan. I am not sure how they came up with that number. The part (from the dealer) is about $900 so they have to be figuring $500 for labor?? Right? That would be at least 6 hours of labor unless they are charging more than the standard rate. Sooooo....how come I replaced mine in my garage in under 2 hours? And 30 minutes of THAT was jacking up the car and putting it on stands. Add to that the fact I paid $645 for an aftermarket part and I saved myself about $750!!
That leaves me with my last issue (I HOPE!). When I replaced the ABC pump, I had to remove the high pressure AC line from the AC pump to get at one of the bolts. I had to remove all the pressure from the system first. I am guessing this released some of the coolant from the system. Now I cannot get the "AC off" light to turn off on the dash. I bought a can of refrigerant to recharge the system but it says to turn on the AC and run it for at least 3 minutes before checking the charge and adding coolant. Is it safe to assume the AC pump is not engaged if this light is on?? If so, how to I engage the pump so I can recharge the system? Also, does this system also service the turbo intercoolers on this engine? I noted that a squeek had started when I took the car out on Friday. It sounded like it was coming from the area of the AC pump. I don't want to drive it if it may be doing some damage to the pump due to lack of lubricant so I will be waiting to drive it until I have this fixed.
Thanks for any advice,
Keith
That leaves me with my last issue (I HOPE!). When I replaced the ABC pump, I had to remove the high pressure AC line from the AC pump to get at one of the bolts. I had to remove all the pressure from the system first. I am guessing this released some of the coolant from the system. Now I cannot get the "AC off" light to turn off on the dash. I bought a can of refrigerant to recharge the system but it says to turn on the AC and run it for at least 3 minutes before checking the charge and adding coolant. Is it safe to assume the AC pump is not engaged if this light is on?? If so, how to I engage the pump so I can recharge the system? Also, does this system also service the turbo intercoolers on this engine? I noted that a squeek had started when I took the car out on Friday. It sounded like it was coming from the area of the AC pump. I don't want to drive it if it may be doing some damage to the pump due to lack of lubricant so I will be waiting to drive it until I have this fixed.
Thanks for any advice,
Keith
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Joined: Dec 2012
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From: Ball Ground, GA (N of Atlanta)
2003 S500 2007 GL450
If you disconnected an AC line and released the refrigerant from the system, the system must be pumped down to a high vacuum before being recharged, and the type and amount of refrigerant added must be correct.
Running the AC compressor with no refrigerant in the system will ruin it in short order.
Too late now, but disconnecting AC lines leads to a world of problems if you don't have the specialized equipment and knowledge to properly service the system.
There is no problem with driving the car until you get the system serviced - the compressor will not be turning, as there is a clutch that will not engage until the computer is satisfied that the refrigerant level/pressures are correct.
Running the AC compressor with no refrigerant in the system will ruin it in short order.
Too late now, but disconnecting AC lines leads to a world of problems if you don't have the specialized equipment and knowledge to properly service the system.
There is no problem with driving the car until you get the system serviced - the compressor will not be turning, as there is a clutch that will not engage until the computer is satisfied that the refrigerant level/pressures are correct.
Last edited by wallyp; Jan 14, 2013 at 10:18 AM.
Thread Starter
Member
Joined: Nov 2011
Posts: 181
Likes: 4
S600
This last one really put my mind at ease. I thought I had screwed up royally. I guess the reason that the AC off light is staying on is the lack of pressure/coolant in the system. I am still not convinced that I did not screw the pooch on this one. There IS a squeak coming from the area of the AC. I have someone coming over who knows what they are doing and has the right tools. I will just let it sit like that until he comes over. Keith
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Joined: Dec 2011
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From: Ontario, Canada
MB 2003 S600. Volvo 2003 XC70.
Keith,
You were mentioning 3 different circulations. But base on your explanation I'm not sure for which system you disconnected the hose:
1, Main coolant circulation:
2, After run for cooling Turbos. This is the 2nd coolant circulation;
3, AC refrigerant.
Seems you are only working on the refrigerant. That means there is nothing to do with coolant.
Please find out which specific one you disconnected then it will be easier for other members to help.
Thanks.
Howard
You were mentioning 3 different circulations. But base on your explanation I'm not sure for which system you disconnected the hose:
1, Main coolant circulation:
2, After run for cooling Turbos. This is the 2nd coolant circulation;
3, AC refrigerant.
Seems you are only working on the refrigerant. That means there is nothing to do with coolant.
Please find out which specific one you disconnected then it will be easier for other members to help.
Thanks.
Howard
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Joined: Nov 2011
Posts: 181
Likes: 4
S600
Sorry for the confusion Howard. I am dealing with the refrigerant at this point. I have obviously disconnected the cooling system several times. Once to remove the radiator in order to replace the ABC pump, then again to replace the radiator, and lastly to replace the fan I had to disconnect the main input/output to the radiator.
However, my issue with the AC is that I had to disconnect the high pressure line from the AC pump and thusly had to release the pressure from the system. The metal tube running from the AC pump runs right in front of one of the bolts on the ABC pump so it must be removed to get the ABC pump off. I think wallyp had the answer for my issue. The guy who services my heater/AC at my home was here when I was working on it and has some experience with vehicle AC also. He mentioned, even before wallyp answered my plea, that I needed to vacuum the system and he even offered to help with it.
I have been sick for almost a week, but when I am better I plan on calling him and getting the help/expertise/tools to deal with the issue. Thanks for chiming in Howard. I can use all the help I can get but I think I am on the right track.
Keith
However, my issue with the AC is that I had to disconnect the high pressure line from the AC pump and thusly had to release the pressure from the system. The metal tube running from the AC pump runs right in front of one of the bolts on the ABC pump so it must be removed to get the ABC pump off. I think wallyp had the answer for my issue. The guy who services my heater/AC at my home was here when I was working on it and has some experience with vehicle AC also. He mentioned, even before wallyp answered my plea, that I needed to vacuum the system and he even offered to help with it.
I have been sick for almost a week, but when I am better I plan on calling him and getting the help/expertise/tools to deal with the issue. Thanks for chiming in Howard. I can use all the help I can get but I think I am on the right track.
Keith
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Joined: Nov 2010
Posts: 2,605
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From: Welwyn, Herts, UK
2006 S600
Watch out guys, the more recent W220's at least had clutchless AC compressors. Depending on the year, you may not be able to simply switch it off. New compressors have variable displacement, with the piston stroke going down to almost zero when AC isn't required. This takes away the need (or benefit) for having a clutch. So the compressor may be running ALL the time. Mine certainly does.
Nick
Nick
Super Member
Joined: Sep 2012
Posts: 690
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From: Montreal, Quebec
2009 E350 4M Avantgarde;mistress 2002 S600; wife 2014 C300 4M
Watch out guys, the more recent W220's at least had clutchless AC compressors. Depending on the year, you may not be able to simply switch it off. New compressors have variable displacement, with the piston stroke going down to almost zero when AC isn't required. This takes away the need (or benefit) for having a clutch. So the compressor may be running ALL the time. Mine certainly does.
Nick
Nick
Search the forums; there is a lot of info on this (HVAC diagnostic menu)
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From: Long Island, NY & SE England
A Mercedes obviously!
*Possible useless post alert*
There are probably a number of reasons why the AC OFF light won't go out but in my case it was, I believe, a bad hydroactive pressure sensor. It was a $280 swap out at the dealer for me so probably about $5 in parts and 15mins of your time
There are probably a number of reasons why the AC OFF light won't go out but in my case it was, I believe, a bad hydroactive pressure sensor. It was a $280 swap out at the dealer for me so probably about $5 in parts and 15mins of your time
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