Is there a member that rebuilds the heater control box, more than just re-solder?

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

Maybe contact James Dean, he works on them and other electronics..


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

There are 3 boxes in the automatic climate control system. One is the push-button box in the dash, which you probably refer to. I think it consists of just buttons, relays for the vacuum vent control valves, and a "user request wheel for temperature setpoint". The "brain" and "blower speed relays" boxes are above the glove compartment. The system also has the temperature sensor (bottom of dash top) and "mono-valve" (water servo-valve in engine bay on firewall).

Describe your problem because the push-button box may be the least likely culprit.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

Thanks for all that info. .
There is 12+ to one side of the mono valve but no ground to the other side coming from the control. The valve is open by default all the time.
Thanks
John

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

So is your problem no heat or heat all the time?

The pushbutton controller applies a ground to stop flow through the monovalve such as when cool air from air conditioning is desired.

It also applies a pulsed ground for controlling the amount of heat.

You can find a schematic in this post:
www.peachparts.com/shopforum/diesel-discussion/366940-w123-auto-manual-climate-control-swap-wiring-help.html

It is hard to follow what many of the symbols mean, so I get lost in the schematic. But, it appears (as post #5 says) that if you click the "desired temperature" knob in the max blue "cool" position, that the mono-valve should get full 12 V, meaning "no hot water flow". You can verify at the valve w/ a multimeter. If you still get hot air blowing, the mono-valve innards need replacing, which is easy but not cheap (~$70). There is a rubber diaphragm that often fails.

When in regulating mode, I think the mono-valve is commanded by the box "electronic switching unit for temperature control", which is above the glovebox and labeled "TemperatureRegular". But, that signal still routes thru the push-button box so cold solder joints there could still cripple it.

__________________
1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans