Hi, I have a 1990 300e and the heater/ac is not blowing air. I can feel the heat and hear that something is on, but air is not blown through the vents. I tried selecting the full white up/down arrows, half white and EC buttons to no avail. Also tried changing the speeds from low, auto, and high to no avail.

How can I test to make sure what needs to be fixed?

Thx

 

In the engine compartment on the drivers side to the rear of the power brake booster there is a cable and connection. Remove the cable from the connection, turn your ignition key on just prior to start, and measure voltage from pins on connection side. You should have battery voltage or near to. If not the problem is with your inside control unit. If so the problem is either the heater fan control, (which this cable you removed goes) or the heater fan motor.

 

I think I found a pic of the control unit and heater motor. Are these correct? Couldn't find anything on the heater fan control.

Thx




[IMG]local://upfiles/12969/AF5149A4B5C649A0950F0AA8AF543373.jpg[/IMG]

[IMG]local://upfiles/12969/C1254FEC2E5947CCAA32329842E80118.jpg[/IMG]

 

If I am not mistaken, the flow of air/ fan activities is regulated by the temperature ****. If you can take the unit out, clean the contact of the temperature ****...

 

I dont know if it makes a difference, but I've tried rotating the temp **** from full cold to full hot and still.... nothing happened.

What I do know is that when the OFF button IS NOT selected , the Rear Defrost button will work. Kinda a weird way of saying it... but what I mean is, the defroster button will only light up the red dot when a fan speed is selected to anything other than off.

So I know something is working right. I just wished the fan would work so I could get some heat in this frigid weather.

Thanks

 

well.... on mine, when I turn the temp ****, the fan kicks in and out depending on the ambient temperature... that's why I suggest to clean the contact of the temperature ****...

 

How difficult is it to clean the contacts?

I finally got to the blower motor. The fans were stiff/stuck, but I oiled them up and they still didn't work. I measured the voltage (blue/red wires) going to the motor and it read 12.4ish. So this means power isn't the problem, right?

Here's the strange thing.... The power measured the same regardless if I had the on or off selected on the climate control unit. ?????????????