Hey guys. I have a 2007 f150 with the 5.4 🤦🤦 my heater quit working on me. I was on my way home one day and had the fan set on full blast and it started acting weird. I would speed up and slow down, speed up slow down as if I was switching it from lowest setting to higbest setting. Then it got really really slow. Now it wont work but when I try to turn on the heat ot sounds like it wants to do something but just wont. Heat, and ac doesnt work. Blower motor? Thanks!

 

Does the heat not work (you said A/C too) or does the fan not work.

Those are 2 different things.
No heat could mean no anti freeze, etc and other major stuff.
It could be a blend door failure.

You seem to be talking about the fan not working more than anything?
Please clarify what quiet working.
Fan speed?
Heat selection has no changes to discharge temperature?
Then you say "it sounds like it wants to do something when you turn on the heat". What does that mean -what did you turn on (or try to turn on)?

 

sorry for the confusion. But yes the fan just wont turn on anymore. Not sure what really to check or start replacing first

 

I'm unaware of the official diagnostic procedure and dont have access to my repair manual at the moment. But, I would verify that the blower motor has power going to it when the switch is turned on. If power to the motor is verified, then I'd feel safe to assume the blower motor has failed.

I have seen other instances of the same problem and the motor was the culprit. One can be purchased relatively inexpeninexpensively off Amazon and their is lots of reference material available on YouTube for the repair procedure.

Hope this helps and good luck!

 

If you choose to replace the resistor, make sure you fully install the resistor before you 'test'. You'll burn up the resistor if you do not have it inserted into the duct system.
Resistor generally fixes when only high speed fan operation works. Probably not for you but in the event you throw parts at it, make sure to install the resistor properly.

Otherwise, check fuses and supply power to the fan if you can.
Or test the wiring at the harness for power before you supply your make shift wiring for a test.

 

I'd replace the blower motor first (I think you have to take the dash out to do this). If you still don't have all your fan speeds after that, replace the resistor.

 

As already suggested, check fuses and inspect resistor (unlikely though if fan is totally dead).

If you move on to blower motor though i would pull and inspect it first. I helped out someone on an explorer where their blower made such horrible noises. Upon pulling blower their were acorns and leaves in there (had been in storage) and once cleaned it was totally fine. I imagine it could have been possible to have been lodged in worse and made it inoperable.

Post back with what you learn and how you fixed.