Front AC blower not working

[John Gouch]

I've seen many posts from people whose front AC blower would stop occasionally. My wife would kick the wires under the glove compartment and it would start again. It finally failed altogether. Following the advice from other owners, I replaced the blower motor resistor. That didn't help. I replaced a 40-amp fuse in the power distribution box under the hood and a 10-amp fuse in the panel under the glove compartment. I also replaced a blower motor relay in the power distribution box. I bought a new blower motor. I plugged in the wires, but I didn't install it yet (It's in a tough-to-reach spot). The new one doesn't work either. What should I try next?

 

[Plati]

Not being critical of your efforts, but I think you are trying to repair by replacing parts first. This is what a bad repair shop does and it can be expensive and even lead to multiple new problems. I know from personal experience. The best way to repair is to diagnose the problem with evidence of the failure. Then replace or repair the known bad parts. Unfortunately to do this you have to know what all the associated parts are and how they work individually and together. It could just be a loose terminal in a connector or a wire that broke.

Hope this helps.

 

[Trainmaster]

The weak point on these systems is the resistor connector, though they usually present themselves when you try to unplug them. The clue that kicking the wires further points to this problem. Unplug it and check it out for continuity.

Check all the connectors for the heating system while you're at it.

Replacement connectors are available. They usually come with crimp connectors, but it's better to solder the wires and shrink-wrap them so you know the splice will carry the full load without heating.

Unfortunately, even the manual heater on the XLT utilizes computer circuitry, which can always be suspect, but the "kick wires" clue tends to eliminate that nightmare.

 

[stamp11127]

Welcome to the site. Which climate control system does your Expy have? They have manual or the fancy EATC.

 

[John Gouch]

Thanks all. I'll be checking connections to see if I can find the problem. I have the automatic temperature control.

 

[Trainmaster]

The ATC is a horse of a different color. I'm sure there's a diagnostic routine and probably a keyboard command that will run diagnostics on that unit's control to determine when it's commanding the fan on and off. Combined with a test light on the motor leads, you should be able to narrow down the problem.

 

[stamp11127]

John how are you with DC electric and wiring diagrams?

 

[John Gouch]

I can follow a diagram OK

 

[stamp11127]

Here you go, have some fun. The blower motor is controlled by a module and is on a 40amp circuit. I would suspect poor connections and undersized wiring first.

 

[Eric W Schweiss]

I agree with connection problem. I bought a used 2017 expy from carmax and had no front blower. They sent it back to the dealer and I wanted to know exactly what was found. I was told the 40 amp fuse had a bad connection and was reset with dielectric grease, that was it, has worked fine since.

 

[John Gouch]

Thanks for the help! It's been raining hard for the last several days so I haven't been able to work on it. I'll try tonight.

 

[Richard Mickelson]

Where can I find the best price on a new blower motor wire harness? That's where my problem is.

 

[mtrebuchon]

Depending on your model year, you may be covered by a TSB on the blower motor pigtail. Ford did the "standard" pigtail replacement on mine back in 2015 free of charge. Then I had the same issue in 2017 and they replaced the entire harness free of charge. No issues since.

 

[Richard Mickelson]

Great looking ride Mtrebuchn! How do I find out if I'm covered by a TSB? My ride is a 2011 Limited. I have to play with the current pigtail way to often to get my blow to work.

 

[mtrebuchon]

https://www.carcomplaints.com/Ford/Expedition/2011/tsbs/

 

[Flexpedition]

Have a peek at 4-wire Motorcraft part# WPT688 to ensure its the correct orientation.

Fixed one on a Fusion couple years ago, no issues since. When I bought the part the interchange guide listed most, if not all, Ford/Lincoln models for the past 10 years. Can't say for 100% Expedition was listed but it probably was.

For what its worth, TSB won't do you much good outside of the warranty period. This is a easy driveway fix that the average Joe can complete in less time it takes the schedule a dealer appointment.



You'll notice its 4 generic black wires, you simply put this side by side with your old plug and match wire #1 with #1, #2 with #2, etc.

 

[Richard Mickelson]

Thank you Flexpedition! This is the information that I was looking for. I'll get one ordered ASAP.

 

[Ron1978]

This is what I had to purchase , $60 at dealership, easy fix to, you can see the burn terminal in my old plug,

 

[Plati]

Thank You.

Does anyone know why these burn?
Will the new one burn or is it "beefed up"?
Is there any way to avoid the burn?
What crimp tool is advised, Electricians Cutter/Crimper?
Have not had this situation <yet> in my 2003XLT

 

[Ron1978]

Thank You.

Does anyone know why these burn?
Will the new one burn or is it "beefed up"?
Is there any way to avoid the burn?
What crimp tool is advised, Electricians Cutter/Crimper?
Have not had this situation <yet> in my 2003XLT

Cutter and crimp tool, I used Klein crumpet, when the blower Resistor burn out or get hot, it melts the connector , making it a loose connection, most likely a mishap on engineering