# Blown fuses **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** suspension, ford, f150\ **Created:** [March 1, 2014, 10:28pm UTC](https://community.cartalk.com/t/blown-fuses/83990 "2014-03-01T22:28:55Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Weeks1](https://avatars.discourse-cdn.com/v4/letter/w/47e85d/32.png) [@Weeks1](https://community.cartalk.com/u/Weeks1)\ **Post date:** [March 1, 2014, 10:28pm UTC](https://community.cartalk.com/t/blown-fuses/83990/1 "2014-03-01T22:28:55Z")
the fuse for the speedometer keeps blowing. I changed the fuse and the circit breaker in Dec. 6 weeks later the fuse blew again, I replaced it and it last another 2 weeks and blew again. What is causing and what might be the solution? ---
**Author:** ![BustedKnuckles](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bustedknuckles/32/25_2.png) [@BustedKnuckles](https://community.cartalk.com/u/BustedKnuckles)\ **Post date:** [March 2, 2014, 5:15am UTC](https://community.cartalk.com/t/blown-fuses/83990/2 "2014-03-02T05:15:44Z")
Something in the circuit is drawing too much power. The circuit needs to be analyzed and any modules on the circuit probed to find the culprit. It could be a bad module or bad wiring. It could even be a bad connector. Electrical issues are notoriously hard to diagnose. Especially today with the large numbers of computer modules and lot and lots of wiring. ---
**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\ **Post date:** [March 2, 2014, 7:09am UTC](https://community.cartalk.com/t/blown-fuses/83990/3 "2014-03-02T07:09:08Z")
Fuses usually supply power to more than one device so the trouble may not have anything to do with the speedometer circuit. A lot of times problems like this are due to chaffed insulation on the wire. You should invest in a factory service manual for the wiring if you are going to work on this yourself. It will pay for itself with this one job. Ebay is a good place to find manuals for a good price. ---
**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\ **Post date:** [March 2, 2014, 8:37am UTC](https://community.cartalk.com/t/blown-fuses/83990/4 "2014-03-02T08:37:35Z")
There are also shops that specialize in automotive electrical systems, in case it isn’t your forte. My wild guess is that you have a chafed wire causing an intermittent short to ground in the speedo circuit or one related. A specialist shop will have the schematics, wiring diagrams, and expertise to track it down. ---
**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\ **Post date:** [March 2, 2014, 8:40am UTC](https://community.cartalk.com/t/blown-fuses/83990/5 "2014-03-02T08:40:03Z")
Check the wiring harness for the vehicle speed sensor. A frayed wire shorting to ground might be the problem.