Climate control no longer working in "econ" mode
 

Climate control is working great on my '85 300d, but only when the left three buttons are depressed. No blower action when 'econ' setting is pressed.

Is this a bad control (pushbutton) unit?

On mine, econ won't work unless I push the defrost button first to get the blower turning. Not sure what's causing that but it's been that way for a couple of years. I've never bothered trying to diagnose it.

Entirely possible, a cold solder or two can have this effect.

Does it work if you select ECON then MAX blower speed? If so, the blower motor brushes might be worn to where they need a "high amp" kick to start spinning.

Sixto
87 300D

Sixto, actually it has been working in the way you describe, just about since I owned the car. Now nothing wakes up the blower motor when in EC mode.

In the other modes (except DEF) the blower takes a very long time to kick in if the fan buttons are on low or auto. Kicks in right away on high, but EC won't respond even if I switch over to it from one of the other settings, once the blower is running.