Failed Digital Heater Control Valve May Cause Poor Heat Output on Mercedes-Benz E500

Problem Description and Possible Solution

A failed digital heater control valve can cause a lack of heat output from the climate control system.

Problem Data
RepairPal Verified
Average mileage: 108,923 (65,000–200,000)
4 model years affected: 2003, 2004, 2005, 2006
23 people reported this problem
Viewing 1 - 15 of 15 comments
I have the same problem no heat or no ac and next day everything works fine. I googled the problem and I found that it was a common problem with e500 2003 to 2005 Now I have ac working but blowing hot air in the back vents. So just purchased a new HEATER CONTROL VALVE (PART# A 211 832 05 84 )for $45.00 on ebay and will be installing at the end of the week. That will take care of the problem Note this is the updated valve by mercedes to replace the original part The difference with the original # and the new is the 5 instead of the 6
Blower works fine but the heat is not coming on at all. When the engine is warm, it maintains around 190 deg F like it should so it is not the engine thermostat.
No heat. Also back seat air is blaring heat on hot days/long drives with back seat controls off and on "low" as possible temp!
1st cold day put on my heater and NO HEAT !Took it to CHANDLER MB they say I have a bad Heater Control Valve, NOT COVERED under my warranty ! So I am looking at $ 498.00 Installed by the Dealer, they say it's a lot of Labor to put in !
David Mesa, AZ
Heat doesn't heat. no heat
The front air blows cold but center back vents blow HOT, I haven't fixed it yet
Heat quit working in front and back of car
Not sure how long I have had this one rides in the passenger seat. The heat on the driver side works perfectly fine, however, the heat on the passenger side is blowing cold air only.
cold here and not heat
Vehicle has no heat only blows cold air. In the summer air conditioning blows heat. Was intermittent now it is constant.
No heat only cold air The problem is not fixed looking for an answer 2004 E500 Mercedes
no heat from front and rear blowers
Once the engine warms up when I turn on the heater it will blow warm for 5 seconds and then blows cold. Not overheating.
no heat blowers blowing cold air when heat is on (not fixed)
Only cold air. no heat.