Blows the number 28 fuse, speed control module

SHARON BODAS

MEMBER
2001 FORD F-350
V10
2WD
AUTOMATIC
145,500 MILES

This truck super duty blows the number 28 fuse when you turn the key to on which causes the cruise control to not work. I don't know if it has a speed control module or if it runs off the OEM. I need to get it figured out ASAP. If it is not in the sensor what else could cause the fuse to blow? If its a short where would the best place to start looking for it be?

Friday, June 21st, 2019 AT 10:28 AM

3 Replies

SCGRANTURISMO

MECHANIC
4,897 POSTS

Hello,

There is a short to ground either in the wire leading from fuse #28, which provides power to the speed control servo, or an internal short to ground in the speed control servo. Fuse are designed to blow when a short to ground happens because of Ohm's Law which governs electricity. If you have a constant (vehicle battery 12V) then if resistance or current go down(resistance goes to 0) than the other(current) must go up(current to infinity). When the current is more than the fuse can handle, it blows, saving a fire from happening. In the diagrams down below I have included a wiring diagram of your vehicle's Cruise Control circuit as well as instructions for tracking down a short to ground. Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

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