E320 2003 W211 A/C Question
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Joined: Mar 2022
Posts: 3
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E320
E320 2003 W211 A/C Question
Hey guys, so I was wondering if anyone has encountered this bizzare issue before. Here is the story: I bought my e320 a few months ago, she is in good shape, although I had to deal with some issues, but nothing major. The A/C had the typical "front seats blows cold, back seats blows hot" issue. The previous owner told me it was the HVAC dual valve that needed replacement and that it was a common w211 issue. I read up here on the forums about it and went to a local mechanic. He topped my freon (700 grams) and changed the abovementioned valve. From what he could read with his diagnostic tools (sadly he didn't have STAR), there were no underlying A/C issues. The HVAC dual valve needed replacement though, as the old one had gone bad. Here is where I should mention that the previous owner had also changed the A/C compressor an year back. Now.. the problem is that the A/C is still blowing cold on the back seat row... except if you turn the settings all the way up to HI, then down to LO - then it starts blowing cold, BUT only for exactly 5 minutes. After said period of time it starts blowing hot again. I've timed it again and again it's exactly 5 minutes on the clock every time. The mechanic washed his hands with some story that "MB implemented this as child protection so that the kids don't get cold if they play with the A/C settings" - I called BS on that, but saw that he couldn't get the job done even if I started pressing the matter. Has anybody encountered this before? I've read somewhere on the forums that there could be a SAM module issue. But it's extremely bizzare.
MBWorld Fanatic!
Joined: May 2021
Posts: 2,524
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Would you mind posting a photo of your AC control unit? To determine if it is a 2 zone, or 4 zone and what interface is available before getting into self diagnostic mode
Thread Starter
Newbie
Joined: Mar 2022
Posts: 3
Likes: 1
E320
MBWorld Fanatic!
Joined: May 2021
Posts: 2,524
Likes: 2,041
From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Start the car,
Start the AC
Set temperatures to LO on all vents, front and back
Set Recycle
Press AUTO left button (or REST & OFF in the video) until the display changes giving you a pair of numbers: two digits on the left side, and two digits on right
Once you are there, scroll the left display using the red arrow up button, log the values on the right, and post them. Log from 00->10
Video ->
I am currently working on my own AC issue, here is the data I have collected https://mbworld.org/forums/e-class-w...ml#post8600518
Start the AC
Set temperatures to LO on all vents, front and back
Set Recycle
Press AUTO left button (or REST & OFF in the video) until the display changes giving you a pair of numbers: two digits on the left side, and two digits on right
Once you are there, scroll the left display using the red arrow up button, log the values on the right, and post them. Log from 00->10
Video ->
I am currently working on my own AC issue, here is the data I have collected https://mbworld.org/forums/e-class-w...ml#post8600518
Last edited by JCM_MB; Jul 24, 2022 at 04:16 PM.
