I drove my truck to work today parked it then when i went to start it to go to lunch it wouldnt start. The lights worked had power but key did nothing... checked fuses and found the 80a 32v? alternator fuse blew. i pryed the top off the fuse and bent it back together then disconneted the red wire from the alternator just to get home... i have been running dual batteries for the winch used the winch yesterday truck ran+started fine... what would cause this fuse to go?
thanks
Kevin

no one knows? <img src="/forums/images/graemlins/scared.gif" alt="" /> <img src="/forums/images/graemlins/confused.gif" alt="" /> <img src="/forums/images/graemlins/scared.gif" alt="" />

it is kind of like asking do you like the color of my shirt.
replace it and be done.

Simply not enough info...

While there are some pretty sharp folks who have read your message, none of them can read your mind, or do tests on your truck from their computer. My best guess is that you almost melted that fuse with your winching, & it was no longer up to normal demands so it failed at an unexpected time. It happens.

Fuses are just chunks of metal engineered to melt when the heat from too high a current passes through them. They are far from precise metering devices. If you had a handful of 80 amp fuses, you will likely find at least one that will let you pull 100 amps for a few seconds, & another that will blow at 70 amps in a half a second.

Don't worry about it unless you blow 2 or 3 in quick succession, then you are dealing with a serious electrical problem.

Dave

when i kept blowing my 80a fuse in my truck it turned out to be that my alternator wire was grounding out. check the wiring going to the alternator for any tears in the insulation and make sure you have all the grounds that your supposed to have connected, connected haha. i went through about 4 fuses before i found out where my problem was. so good luck.

Fuses also age, and degrade in capacity with time. If your replacement lasts a long time, you can have some confidence that was it. But it is likely due to a real overcurrent condition.