1977 Ford F150 Accessory saftey relay

1977 FORD F-150
160,000 MILES • V8 • 4WD • AUTOMATIC
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44TRACTORMAN
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I have 77 ford f 150 and the a/c heat blower will not run, with a new accessory saftey relay installed. The old one got hot (for unknown reason) and melted a terminal out. I bought new one and installed it, three prongs and three plugs only one way to fit. Ok when this would not work I used a jumper wire to "cross two of the wires in place of the realy and it came on and seemed to work fine, however the jumper wire was getting a little hot and I dont want to burn up my truck, New fuses,new relay and out of ideas.Thanks
Nov 23, 2009 at 10:56 PM
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JACOBANDNICKOLAS
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Is the switch good? Also, have you checked how many amps the motor is drawing? I question if the motor is bad (still runs) but caused the melt down. You may want to check the switch itself.

Let me know what you find.
Nov 24, 2009 at 6:39 AM
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44TRACTORMAN
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checked amps on old fan after i removed it it was pulling 4.8 to 4.9 amps new one in same test mode pulled 2.3 2.5 i have not finished installing it yet to see if it will work correctly but old one looked melted in and around the windings. this problem is a pain in the butt to get to and remove to fix. will let you know what else i find.
Nov 28, 2009 at 1:20 PM
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JACOBANDNICKOLAS
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Something tells me that is the problem. I know they are a pain. You should try replacing one on a newer F150. THe entire dash has to come out.

Let me know how it goes.

Joe
Nov 28, 2009 at 2:05 PM