Blend door issues

[Mopar1973Man]

I've been fighting a blend door issue where if you turned the temperature up to warm up the cab and later want to turn it to a cooler setting the door wouldn't move. You had to turn it up hotter and then quickly down lower and it would start to cool down. Now Being I've never done a heater treater yet I was thinking the shaft broke and hanging it up. 

 

I grabbed Mark and asked him for an offset Phillips driver. With little patience, I managed to remove the two Phillips screws and removed the stepper motor for the blend door. I was shocked my shaft coupler was still going strong.

 

 

Then I popped open the steeper motor lubed the gears with some fresh grease and then pulled the brass contacts out a bit for the motor to rest against for power. Closed it up and just plugged in the stepper motor without installing it. Turn the key on and the HVAC controls to like Vent. Now rotate the temperature control to hot and cold to check movement. I found that the plug was not quite getting it and gave it a good squeeze and Presto! the problem is now fixed. I did go ahead and take a razor knife and cut the foam pad back to give my fat fingers a spot to get the back Phillips screw back in.  After installing I did the same thing again and made sure the door swung both directions without hanging up. 

 

Sometimes you just gotta give that sticky wheel a bit of clean up and grease.