Blower motor slowed down then it would speed up it quit for a few seconds

2006 FORD F-150
175,000 MILES • 5.4L • V8 • 4WD • MANUAL
Avatar
DALESAAL
  • MEMBER
  • 1 POST
I have replaced the blower motor and the blower motor resistor. It was working on all settings, and I set it on auto A/C it slowed down then it would speed up it quit for a few seconds then went on high then it just stopped. Like I sad the motor is new, and it has a new resistor, it did the same thing with the old motor. Please help. It is a automatic transmission, not manual.
Aug 24, 2020 at 11:36 AM
Advertisement
Avatar
KASEKENNY
  • ✓Experienced Mechanic
  • 18,907 POSTS
Unfortunately, we need to act like we we haven't done anything yet. We can't assume that the blower motor or resistor is not the issue. So I attached the wiring diagram and we need to check power at the motor and then follow it back through the system in order to find where we have power and where we do not.

I would suggest jumping 12 volts to the blower motor just to make sure it turns on. If not then it has failed.

Just to be clear, did this fail the same way the last one did?
Images (Click to enlarge)
Professional Diagram for 2CarPros Members
Click here to log in and view diagram.
Professional Diagram for 2CarPros Members
Click here to log in and view diagram.
Apr 19, 2021 at 4:11 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.