2010 Fusion Hybrid with Dual Temp Control blows cold air on passenger side when calling for heat *partially fixed*

[FFHybrid]

Hi all,

 

I have a 2010 FF Hybrid with Dual Temp Control.  As the weather just cooled down here, I turned on the heat and noticed the heat on drivers side works fine but the passenger side was blowing cold air.  I instantly thought that the blend door motor was bad so I ordered it thinking it would be an easy fix.  Looking at the removal instructions, it showed that several items needed to be removed just to replace this small part so I decided to dig a bit deeper. 

 

I noticed I could not hear the passenger side blend door moving at all when I varied the temperature.  I also put my finger on the actuator to see if I could feel it moving....nothing.  However, the drivers side was working and I could hear it moving. 

 

I removed the 5 pin connector on the passenger blend door motor and took some measurements.  I was looking for 12V between pins 1 and 2 but only measured between 3V and 4V max.  I then checked the POTS pins and had 5V there.  I wanted to see if the blend motor was actually bad so I stripped part of the wires (Pin 1&2) and hooked up a 9V battery and added some leads to make the connection.  Sure enough, the motor moved and opened to allow heat.  I was relieved but also somewhat stumped. 

 

Since I had solved the issue temporarily I took it for a test drive and got nice warm heat from both driver and passenger side and came home.  I turned the car off and back on and felt cool air blowing again from the passenger side.  I checked the actuator and noticed it went to a "home" position on its own and did not stay in the heat mode that I manually put it into.  I then applied 9V battery again to make it go back to heat position and removed the power connector from the motor.  At this point, the heat is working fine however I will only be able to change the temperature on the drivers side.  

 

My question is, does it seem likely that the DATC is defective at this point? Is the DATC what sends the voltage to the blend motor?  The DATC is showing the temperature modifications (on digital readout) when I change the passenger side temperatures.  

 

Or should I check something else out?  I'd hate for it to be a fuse or something small like that.  

 

Thanks to @eGuru for some excellent troubleshooting tips in this previous threads that I was able to follow.  

 

[eGuru]

Measure the voltage on the center pot pin (with respect to ground) at the travel extremes and while the actuator motor is moving. 

You should see roughly 0.5V to 4.5V.

btw - driving the actuator motor to its travel limits using a battery can wreck the pot. It's okay to do it while the actuator is still mechanically coupled to the damper because it can't over travel . If it is mechanically uncoupled it can over travel. So if you are in the process of installing the new actuator, don't "test" it before coupling it up.

Edited November 10, 2020 by eGuru

[FFHybrid]

I can't get the actuator motor to move at all when it's plugged in unless I bypass with the battery.  

 

The only test I did on the new actuator motor was to plug in the harness while the motor was not mounted (just hanging down) and changing the temperature to see if I could get it to move.  The motor didn't move at all.  So my next step was to bypass the wiring and use the battery to get it to move.  

[eGuru]

If the new blend door actuator did not move when plugged into the harness (but not physically attached), then you can suspect that the HVAC controller or the wiring is the cause.

Meter the  resistance to ground, at the connector, of the wire that connects to the center pot pin. If you have recently had your passenger air bag replaced, that wire may have been broken in the process.

[FFHybrid]

Thanks I will check out the resistance to ground later today.  I am suspecting its the HVAC controller at this point rather than the wiring because nothing has been touched near that area.  The passenger airbag is the original.  The only odd thing that happened recently (a few months ago) was the car completely died and I had to jump it but I can't imagine that would have had any negative impact.    

 

Is the HVAC controller part of the DATC module?  Similar to this.  https://www.ebay.com/itm/Temperature-Control-AC-Main-VIN-A-8th-Digit-AE5H18C612AE-Fits-10-11-Milan-OEM/174467075708?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

 

If so, how do I get the correct part # for what I have without having to rip mine out first?  Mine does not have leather or heated seats which I've seen some modules have that component button.  

[eGuru]

If the ebay picture is similar to yours and it says it is for 2010-2012 Fusion in the ad, then it should be fine.