Ns091677

I have a 2004 S600 v12 that blows very hot air out of the rear heater for backseat but will not blow hot air through any front vents. I set it on auto or manual and it make no difference the air is comming out lukewarm in the front vents and is blowing cold when the car is stopped, when driving it blows lukewarm air. My mechanic has said no codes showing for actuaitor motors and he doesnt hear and clicking noise, he has checked the duo valve and said its working, he has flushed out my heater core. He cannot figure out what the cause is, the only thing he thinks we could try but no garantee is to repkace thermostat (I dont think this would work cause the heat blows hot in the rear heater and the car does not overheat) or he sais the car could have air pockets causing the problem and that only a dealer has the proper tool which he called it an octopus tool which he said is special tool for flusing out a mercedes cooling system. Does anyone have any advice or ever heard of such a problem? the S600 is not common so its hard to find anyone who knows anything about them. My mecanic worked for benz for several years but had only worked on two S600's.

ibeforreal

Read through some of these threads. I'm sure the S600 is set up the same way as the S500.

https://mbworld.org/forums/s-class-w...-air-only.html


http://www.justanswer.com/mercedes/7...t-working.html

wallyp

If you can find someone who has DAS and knows how to use it, there is a very extensive set of diagnostic tests that check virtually every piece of the system.

cynthanny

Looking for suggestions to find the problem. Put a new front blower in and now the heat is almost non existant. It gets a bit warmer when on the gas and gets cold at idle. Please help
Thanks

kraut56

The duo valve is working, but the pump on the duo valve is not.
The pump is needed at idle to get warm fluid to the heater.
Bet you when you rev up the engine or drive on the highway everything is heating nicely.
Forget playing with the thermostat;on the V12 it's a fortune.
Good luck!