126 - No heat at floor
 

84 380SE, 95K miles, its a cherry (a bright red 126!). When in heat mode with temperature wheel at full heat, i get full heat at the windshield. When I turn the wheel from hot to cold there is a point about halfway where it will become 100% air flow from center dash vents (cool air). Doesn't matter if i'm in economy or compressor mode. After searching the threads, I suspect either defrost element behind the radio or CCU (solder joints hopefully) Any consensus on which it is?

Did you first try closing the dash vents using the 3 sliders? Generally speaking, even if the pods for the dash flaps are leaking, you will still get a fair amount of volume from the floor vents if the dash vents are closed.

With temperature wheel at hot mode all hot air is coming out of defrost. Only when i turn the wheel to cool does a flap cycle and allow air to come out of center vents. This is cool air coming out of center vents and will do me no good in the floor area when i'm looking for heat.

I've mentioned it a couple times. Check the changeover valves located under the panel to the right of the radio. Test each one for electrical continuity. They burn out over time, leaving the heat/cool flaps in their default positions. You should check them first before trouble-shooting the vac elements. Two of mine were burned out, and caused most of my ACC problems (the other culprit being a bad sampler fan).

thanks. Are they individually mounted or are they a one piece unit as in my 560SL. Also, does anyone have a vaccum element schematic for the 84 126, I can't get but halfway in to braingear before it quits responding.

They are individual. There are 5 or 6 of them mounted on a metal bracket.

Still troubleshooting
 

only element i find next to accelerator has a green vacuum line. Is this the pod for the floor flaps? Sure would like to have a good HVAC vacuum schematic for 85 380SE. Searched and tried braingear, no luck. Does anyone know if my schematic for 87 560 SEL is good for 85 380SE?

Join the club... :) I think all of us have 380SE models (mine is a 1985 - manufactured in October of 1984) and mine is the same way. No matter the setting, I get most heat in the defrost, but I still get quite a bit on the outside dash outlets. I just turned them completely downward and they are pretty sufficient at warming the legs/feet. Of course it does not get all that cold here in the winter (and it looks like everyone else here posting also lives in mild winter climates), but I am sure if I lived in the north or a colder climate, I would be more concerned, but its not enough of a problem for me to bother fixing it now. I could understand though wanting it to work perfectly on a otherwise mint car (which mine is not). :)
My A/C does not work, but I am assuming if it did... all air comes from there too?

Seems like this is one of the first things to fail on these cars. I think a recall is in order. :D Another thing I have noticed- not sure if it is normal, but if I actually put the mode on defrost, the air comes out at full speed- not matter the fan speed I set it on. Any other mode setting and it lets me select the speed with the fan speed switches, or it lets the automatic work. The HVAC is the last of my concerns now anyway, what, with something busted on my power steering system. To the shop next week I suppose..... :rolleyes: 268,300 mile and counting.....

Good luck!

Try to unplug the power supply to the heater/waterpump. If the pump has seized up it may throw the cc into faut mode and will give you warm defrost all the time. Good luck
Paul

What "pump" are you referring to that may have seized?

Econ heat diagram
 

I just went through this last weekend... I had a leaky valve and a bad pod for the leg flap. I also had to resolder my CCM module.

http://zbat.net:8000/tmp/heat.jpg

Which element controls the air that goes through the channel under the dash and out to the doors?