Bad Blend door actuator? Or Electrical Issue?

[RyanEAS]

So here's the skinny. I have an 04 TB EXT. Rear heat hasn't been working. I suspected it was the rear heater core, but I was able to rule that out pretty quickly. I narrowed it down to the blend door actuator. I swapped out heat/cool blend actuator with the directional actuator (the one for air to come from the top/bottom/both). The suspect actuator won't work. Great! Problem solved, right? WRONG!!!

The GOOD actuator (the directional one) definitely works. When I plug in the GOOD actuator into the plug for the heat/cool blend door, it no worky. So..... Thoughts? Would disconnecting the battery and/or checking the fusebox be my next step? What exactly does the whole "Calibrating" thing do after you disconnect the battery? And for the record, I have two little ones, so heat is definitely needed. Thanks in advance fellas!

 

[Sparky]

Calibrating the door runs the actuator sweep from one extreme to the other, so then it knows the limits of every actuator and the position of it. (this is why a flaky actuator may fully die if run through a recalibration, as worn gears might let it try going past the stops and then get jammed up.)

Not all actuators are swappable, even though they might look the same. Make sure the part number is identical. If they are, go ahead and pull the HVAC fuse(s) for a couple minutes, put them back, and turn the key to run (don't start) and let it sit for a couple minutes to recalibrate everything.

 

[freddyboy61]

The two actuators are the same part number, so if either one does not work in one location, the problem is with the control module or a wiring issue.

 

[RyanEAS]

Well I'm pretty sure I got it figured out today. After some trial and error, I got both actuators working again. I disconnected the negative battery terminal for about an hour, and also pulled the HVAC-B (10amp) fuse underneath the Left-Rear seat. I re-connected the battery cable, turned the key to run (engine off), THEN put the fuse in. It went through it's calibrating process. Then I would pull the fuse again, wait a minute or two, then plug it back in. It calibrated again, and so on. I did that about a half-dozen times. After that, I tried all possible settings of hot, cold, fan speed, top or bottom vents, controls from the front, the rear, etc. Everything worked. So now I get to return the actuator I ordered (if amazon ever decides to deliver it!) Thanks for help guys!

 

[Reprise]

I think you're better off keeping it, especially since it can replace more than one location's actuator. Because one *will* fail at some point.