My big bear will start but it blows the 30amp fuse every time. I can replace the fuse and restart and drive it but I'm afraid to because I don't want to chance burning the harness up. Anyone know where I can start checking for the short ?

 

The fact is that the fault can be anywhere between the main fuse and any sub fuses. However the voltage regulator must be a suspect. I get a 12v test bulb and put it in place of the main fuse, if it glows without the ignition switch on, the fault is between the fuse and the switch. Disconnect the regulator, if the light goes off you have found the fault and need a new regulator. The light will come on anyway, when you switch on the ignition and a fault beyond here can be in many different circuits, so a wiring diagram is needed.

 

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