I was just wondering if anyone could solve my problem. I have a 97 F-150 and the heater blower stays on even though the ignition is turned off. I would suspect that a relay is bad. If anyone knows where this relay is, or if you have any other idea of what may be the cause of this problem, a reply would greatly be appreciated.

Thanks

 

If the blower is staying on with the key off, it's not just a stuck relay. All power should be off to the blower motor (including the relay). Sounds like the motor may be getting power from somewhere else (possibly a short). Check the Function Selector Switch Assembly. And wiring to the Blower motor and motor relay. Sorry I don't have the wiring diagrams for a '97, but I do have them for '01. If you think it will help I'll post the diagrams in my Misc. Photo Gallery.

 

Are you positive that all power will be off even with the key in the off position? I thought the relay always had power, at least the one that goes to the blower motor.

 

DOH!

You are quite correct, mscott! The line going to the blower relay IS hot at all times. I should have looked at the diagram more closely. The line controlling the blower relay is only hot in the "RUN" position of the ignition switch. So, indeed, a stuck relay could be the problem that equilibrium13 is experiencing. In the '01 Wiring Diagrams, that relay is located under the dash and is called the "Blower/Flasher Relay Block".

Thanks for the correction - I'll be more careful in the future!

 

I had the same problem in GM car several years ago. 91 Buick! turned out to be a bad transistor that controled the relay to the blower motor. On that car it was located under the hood next to the blower assembly. I believe on the F150s its under the dash on passenger side in a very out of the way ,(hard to get at place)
Hope this helps and Happy Holidays

 

Thanks for the ideas....I think I'll just try to replace the relay, hopefully its not too hard to get to and hopefully thats all the problem is.

Thanks

 

Bullseye670 here. I was looking for the blower motor relay and came across this. Its identical to my problem.
I still need to find the relay. My haynes manual just says under the dash.
I heard it clicking on and off- went for a flashlight and it stopped.
Could someone give me a specific location????
bullseye670.............