blower motor will not stop until I disconnect battery

2002 FORD F-150
209,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
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RICK WATZ
  • MEMBER
  • 1 POST
Will not stop until I disconnect battery and reconnect. All controls work when truck is running. Radio turns off sporadically. Rain seems to cause the trouble.
Oct 6, 2018 at 10:41 AM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Hello,

It sounds like the blower motor relay is stuck on. Here is a wiring diagrams so you can see how the system works and a guide to help you test the relay with the relay location as well:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Check out the diagrams (below). Please let us know what happens.

Cheers, Ken
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Oct 8, 2018 at 10:41 AM
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