AC is Only Cold on the Driver Side
Thread Starter
Junior Member
Joined: Aug 2017
Posts: 26
Likes: 2
E320
AC is Only Cold on the Driver Side
2003 E320 Sedan 4Matic. Trying to get the car in better shape for my son to drive. Noticed that when I turn on the AC (either via temp dial or manually adjusting the speed), the air on the driver side isn't hot, but not that cold. When I feel the air on the front passenger side, it's much colder.
1. Are there separate refrigerants for both sides? I've had a shop had refrigerant/freon to an older car before, and the air was much hotter (though there weren't separate driver and passenger side zones).
2. Is it an easy fix?
3. Can I fix it myself?
Thanks for any advice out there.
1. Are there separate refrigerants for both sides? I've had a shop had refrigerant/freon to an older car before, and the air was much hotter (though there weren't separate driver and passenger side zones).
2. Is it an easy fix?
3. Can I fix it myself?
Thanks for any advice out there.
Thread Starter
Junior Member
Joined: Aug 2017
Posts: 26
Likes: 2
E320
Super Member
Joined: Apr 2007
Posts: 633
Likes: 48
From: USA
2006 E320 CDI
You are low on 134a, get gauges as loaner from autozone, high side needs to be 200psi when engine is running, and AC is selected to coldest setting, with ambient outside temp around 85F. Make sure hoses are purged of air before 134 is added to low side of system. Do not rely on gauge on 134a can, besides it would be on the low side when attached.
Last edited by ot1; Aug 2, 2019 at 10:39 PM.
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From: V E G A S
1922 Ford Model T / no OBD
Unless you have climatronic with REST button, you will need a scanner to troubleshoot the system.
About 90 seconds job to do it right, although the iCarsoft I am occasionally using is slow as a turtle.
About 90 seconds job to do it right, although the iCarsoft I am occasionally using is slow as a turtle.
Newbie
Joined: Jul 2011
Posts: 10
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E320 2002
You are low on 134a, get gauges as loaner from autozone, high side needs to be 200psi when engine is running, and AC is selected to coldest setting, with ambient outside temp around 85F. Make sure hoses are purged of air before 134 is added to low side of system. Do not rely on gauge on 134a can, besides it would be on the low side when attached.
What is the pressure on the low side need to be?
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Super Member
Joined: Apr 2007
Posts: 633
Likes: 48
From: USA
2006 E320 CDI
Doesnt matter on low pressure side, read the high side before you put refrigerant in, you must have some in since your getting one side cooling,but not cold I suppose, its probably around 140psi, therefore you dont have a major leak, so purge air from lines and add in gas not liquid, until you read 200psi, at 85F, if you go a little over 200 psi not a huge concern, but add in gas slowly. I recall low side when charged around 40psi, but its the high side thats important. Btw gas or liquid is the position of the can in relation to the discharge port on the can. And you know that the 134a always alWays always, goes into the low side port, which is the suction side of the compressor, wear leather gloves and safety glasses. If you never used a gauge set, make sure all valves are closed on the manifold, than attach blue and red hoses to vehicle and that the valves are closed on the hose ends. When adding 134a you will be opening the blue valve, never the red valve. I fill from a large cylinder which attaches to the yellow port, when filling you open that valve too. If you fill from a 1lb can the blue hose on the gauge set wont be connected, the hose included with the can will connect to the low side.
Last edited by ot1; Aug 11, 2019 at 02:29 PM.
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