FIX: Rear Climate (4-Zone) blowing only hot or cold.
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Joined: Feb 2016
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08 S550 4Matic w/ AMG Pkg & P3
FIX: Rear Climate (4-Zone) blowing only hot or cold.
** I am not responsible for any damage your may incur to yourself or vehicle ** This post is meant as a guideline to possibly fix an issue you may have that's similar to mine.
WARNING: COOLANT IN LINES **DO NOT ATTEMPT THIS REPAIR WHILE VEHICLE IS HOT**
OK everyone, as the thread title says, for those of us with the 4-Zone Climate and have experienced the system in the back vents blowing really hot or cold air out of one or more vents...here's what I did to fix my issue.
My Problem:
I have a 2008 S550 w/ 4-Zone climate and noticed scalding hot air coming out from the rear center left vent while the right vent was only cool not cold. Now, it didn't matter on what setting I had the climate on HI,Low,Auto,Manual...it was still the same, extremely hot air coming out.
Repair Time: 20-30 minutes
* Skill: If you can change your oil, you can do this!
* Tools needed: Pliers (for hose clamps),8mm & 10mm socket, ratchet
* Part Needed: MB Part# 2208300284 **Approx. $300 from MB**
(This part was apparently used on the W220 also, as I got mine on ebay for $50 which was pulled from a 2002 S600). PN was the SAME as my 08...I check the PN on my car before I bought. (Be careful when buying anything used).
* Coolant to top off with.
I searched the forums and internet and came across this water valve people were calling "DUO VALVE" OR "WATER VALVE". Most of the posts don't have a "fixed" solution. So hopefully this thread helps everyone find the info much more easily. The posts I've found says that this valve is located under the windshield wiper arm. Well, while this is correct, it doesn't apply to us who are experiencing this problem only on the rear climate. The "DUO OR WATER VALVE" Located under the wiper arms are for the FRONT climate control (which I should add, also controls the vents in rear ON THE PILLAR POSTS.
On models with the 4-Zone climate, there are actually 2 "DUO OR WATER VALVES". The one we need to look at and will be replacing in this post is actually located in the RIGHT FRONT FENDER. Now, I did find a post that had a picture of where this part is located, but I can't find it any longer. It looks like if you remove the (3) 8mm bolts & (1) 10mm nut holding the under portion of the front wheel liner towards the back, it can be accessed. I chose to remove the passenger front wheel and the other (3) 10mm nuts & (2) push clips holding the rear portion of the front wheel liner and completely remove it for much easier access. You will now see the "DUO OR WATER VALVE" in the lower corner of the fender which is held in place by (2) 10mm bolts.
Remove bracket from old pump. Next using a pliers, squeeze the clamp (I did one at a time), slide it back and then remove the hose and place it onto new part. (SOME COOLANT WILL SPILL OUT, MAKE SURE YOU HAVE SOMETHING TO CATCH IT IN). Repeat the last steps for the other two hoses. Now put everything back and bolt it up. You're done!
**PICTURES WITH BLUE BACKGROUND ARE THE $50 REPLACEMENT I PICKED UP ON EBAY** The other two pics is the old part removed.
WARNING: COOLANT IN LINES **DO NOT ATTEMPT THIS REPAIR WHILE VEHICLE IS HOT**
OK everyone, as the thread title says, for those of us with the 4-Zone Climate and have experienced the system in the back vents blowing really hot or cold air out of one or more vents...here's what I did to fix my issue.
My Problem:
I have a 2008 S550 w/ 4-Zone climate and noticed scalding hot air coming out from the rear center left vent while the right vent was only cool not cold. Now, it didn't matter on what setting I had the climate on HI,Low,Auto,Manual...it was still the same, extremely hot air coming out.
Repair Time: 20-30 minutes
* Skill: If you can change your oil, you can do this!
* Tools needed: Pliers (for hose clamps),8mm & 10mm socket, ratchet
* Part Needed: MB Part# 2208300284 **Approx. $300 from MB**
(This part was apparently used on the W220 also, as I got mine on ebay for $50 which was pulled from a 2002 S600). PN was the SAME as my 08...I check the PN on my car before I bought. (Be careful when buying anything used).
* Coolant to top off with.
I searched the forums and internet and came across this water valve people were calling "DUO VALVE" OR "WATER VALVE". Most of the posts don't have a "fixed" solution. So hopefully this thread helps everyone find the info much more easily. The posts I've found says that this valve is located under the windshield wiper arm. Well, while this is correct, it doesn't apply to us who are experiencing this problem only on the rear climate. The "DUO OR WATER VALVE" Located under the wiper arms are for the FRONT climate control (which I should add, also controls the vents in rear ON THE PILLAR POSTS.
On models with the 4-Zone climate, there are actually 2 "DUO OR WATER VALVES". The one we need to look at and will be replacing in this post is actually located in the RIGHT FRONT FENDER. Now, I did find a post that had a picture of where this part is located, but I can't find it any longer. It looks like if you remove the (3) 8mm bolts & (1) 10mm nut holding the under portion of the front wheel liner towards the back, it can be accessed. I chose to remove the passenger front wheel and the other (3) 10mm nuts & (2) push clips holding the rear portion of the front wheel liner and completely remove it for much easier access. You will now see the "DUO OR WATER VALVE" in the lower corner of the fender which is held in place by (2) 10mm bolts.
Remove bracket from old pump. Next using a pliers, squeeze the clamp (I did one at a time), slide it back and then remove the hose and place it onto new part. (SOME COOLANT WILL SPILL OUT, MAKE SURE YOU HAVE SOMETHING TO CATCH IT IN). Repeat the last steps for the other two hoses. Now put everything back and bolt it up. You're done!
**PICTURES WITH BLUE BACKGROUND ARE THE $50 REPLACEMENT I PICKED UP ON EBAY** The other two pics is the old part removed.
