Rear Climate Stuck on Constant Heat in 2013 S550
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Joined: Aug 2019
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S550
Rear Climate Stuck on Constant Heat in 2013 S550
Hi
I have 2013 S550 with electronic rear climate which got stock on High Heat. Adjustments work but for any setting its always blowing High Heat.
Any suggestions how to fix this?
Thank you
Adrian
I have 2013 S550 with electronic rear climate which got stock on High Heat. Adjustments work but for any setting its always blowing High Heat.
Any suggestions how to fix this?
Thank you
Adrian
Member
Joined: Jul 2016
Posts: 108
Likes: 23
2018 S450 4Matic, 2020 GLE450 4Matic, 2010 S550 4Matic(sold), 2012 ML350 4Matic(sold)
Is it blowing hot on both sides of the rear or just one?
Very recently I had this same issue on my 2010 S550 and the problem turned out to be a failed duovalve in the right front fender behind the wheelwell.
Mine had only partially failed and was blowing cool on one side, but scalding hot on the other.
Have you also noticed your center console getting hot against your leg during a drive which is 20 minutes or more?
Tom
Very recently I had this same issue on my 2010 S550 and the problem turned out to be a failed duovalve in the right front fender behind the wheelwell.
Mine had only partially failed and was blowing cool on one side, but scalding hot on the other.
Have you also noticed your center console getting hot against your leg during a drive which is 20 minutes or more?
Tom
Thread Starter
Newbie
Joined: Aug 2019
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S550
Thank you for your input.
It starts blowing little colder on one side in the back, but very shortly after both are super hot, and yes even if the rear is completely off center console gets really hot, very quickly. Would you mind explain in little more detail what this "duovalve" is? and where exactly it is located? Can you take a quick pic? did you have it done at dealer or did you fix it yourself?
Thank you so much for your help
Adrian
It starts blowing little colder on one side in the back, but very shortly after both are super hot, and yes even if the rear is completely off center console gets really hot, very quickly. Would you mind explain in little more detail what this "duovalve" is? and where exactly it is located? Can you take a quick pic? did you have it done at dealer or did you fix it yourself?
Thank you so much for your help
Adrian
Member
Joined: Jul 2016
Posts: 108
Likes: 23
2018 S450 4Matic, 2020 GLE450 4Matic, 2010 S550 4Matic(sold), 2012 ML350 4Matic(sold)
Adrian,
I have found the 4-zone climate control package to be a fascinating design.
The "guts" hidden under the center console consist of an AC evaporator, a blower, multiple temperature sensors, multiple control flaps and servos, and 2 separately circulating heater cores.
The duovalve controls the flow of hot coolant to each of the individual heater cores.
When the duovalve functions properly it appears to RESTRICT the flow of hot coolant to the rear system.
When it fails, hot coolant flows freely whether you are asking for heat or not.
Yes, I replaced mine myself. It is located between the right front wheel and the right front door.
Check out your right fender and you will see there is an area about a foot long between the wheel and the front door.
The valve is located behind the plastic inner wheel well.
Remove the right front tire and the rear half of the plastic wheel well and you can see the valve.
2 electrical connections and 3 hose connections. Very straight forward if you are somewhat mechanically inclined.
PM me and I will send you some pictures.
Also, I will let you know where I found the best price on the valve.
I would check yours to be sure it is the same before ordering, but it likely is as both our cars are W221.
Tom
I have found the 4-zone climate control package to be a fascinating design.
The "guts" hidden under the center console consist of an AC evaporator, a blower, multiple temperature sensors, multiple control flaps and servos, and 2 separately circulating heater cores.
The duovalve controls the flow of hot coolant to each of the individual heater cores.
When the duovalve functions properly it appears to RESTRICT the flow of hot coolant to the rear system.
When it fails, hot coolant flows freely whether you are asking for heat or not.
Yes, I replaced mine myself. It is located between the right front wheel and the right front door.
Check out your right fender and you will see there is an area about a foot long between the wheel and the front door.
The valve is located behind the plastic inner wheel well.
Remove the right front tire and the rear half of the plastic wheel well and you can see the valve.
2 electrical connections and 3 hose connections. Very straight forward if you are somewhat mechanically inclined.
PM me and I will send you some pictures.
Also, I will let you know where I found the best price on the valve.
I would check yours to be sure it is the same before ordering, but it likely is as both our cars are W221.
Tom
