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Q: Fuse blown

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My car won't start. It keeps blowing a fuse (30a fuse) in main box as soon as I try and start it. Most be a short somewhere.

A: Yes this is most definitely a short. A 30 ...

Yes this is most definitely a short. A 30 amp fuse is a large fuse, and in your vehicle it feeds the engine control module relay. A short means that a power wire is going to ground. This is usually caused by insulation that is worn, or a wire that is is cut and the bare part of it is touching metal somewhere. Finding shorts in vehicles can be tricky and should be done by a qualified mechanic. The mechanic should be able to isolate the circuit with the problem and replace any fuse(s) if necessary.

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