speedometer does not work half of the time?

1999 FORD F-250
208,000 MILES • 7.3L • V8 • TURBO • 4WD • AUTOMATIC
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DERIC MORROW
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  • 1 POST
On my truck by speedometer does not work half of the time and then sometimes when I hit the brakes the speedometer will either jump up or jump down depending on whether it's working or not also my overdrive does not work when the speedometer does not work my cruise won't work when nothing is working either neither will my odometer can you help me
Jan 13, 2015 at 1:01 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
scan for codes it may be a bad speed sensor or wiring issue to dash or dash itself.
Jan 13, 2015 at 1:42 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
I would check the electrical connector at the rear on the instrument cluster for corrosion and If that is okay here is the location for the VSS which generates the signal for the speedometer. The sensor is in the tail housing for the transfer case. Check out the images (below). Please let us know what happens.
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Nov 6, 2024 at 1:49 PM
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