# Blowing fuse on Craftsman rider mower??



## garfield306 (May 25, 2012)

I have a Craftsman riding mower with 15.5 Kohler engine and 42 inch mower deck that has developed electrical issues. 
The battery was replaced this spring and worked well for several weeks until I found it dead. I jump started it (off car battery) and it worked well. I pulled the key after I was finished (thought the kids may have left it on), but the battery was dead again the next week. 
I went to jump it again, and this time accidentally had the jumper cables switched on the car battery. I changed the cables to the proper position, but nothing, no clicking. Unhooked the cable, turned the key, and heard a click. Found a 30 amp fuse blown. Replaced the fuse, still totally dead. Rehooked jumper cables, turned the key, and the fuse blew again. 

What is causing the fuse to blow? What caused the battery to die? Any thoughts on where to start would be appreciated. I did a cursory look at the wires and found nothing obvious. I can put up with jump starting the battery or replacing it if it is bad, but the blown fuse has me stumped. 

Thanks so much for your help.


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## garfield306 (May 25, 2012)

Update: tested the battery and they told me one of the cells is dead, so I will get another battery. Not sure if that will fix the problem though.


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## paulr44 (Oct 14, 2008)

Yes, a bad battery can cause a fuse problem. The charging system is trying to overcompensate, so the amperage is maxed out.
Also, a corroded fuse HOLDER can cause this problem...bad connections = high ohmic resistance = charging system thinks it needs to send more and the result is the same. A corroded or poorly grounded regulator can cause this too.
Paul


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## garfield306 (May 25, 2012)

Thanks for the reply. I put in a new battery, turned the key (not even to ignition) and the fuse blew. 

Does this mean bad grounding? Does that explain the dead battery as well? Any other ideas?


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## paulr44 (Oct 14, 2008)

That indicates a short (to ground). You'll have to test circuits with a multi-meter to see what's grounding. If you don't have one or have the knowledge, there's another way, which I'll explain...

Disconnect the keyswitch plug, and using a pocket screwdriver or other small probe in the plug sockets by each terminal you'll see a "T-Bone" by each female terminal. There's a tang in that t-bone, you push the probe/screwdriver down onto it and you can pull one wire out at a time, reconnect the plug and re-test to see if the fuse blows.

ONE OR TWO OF THE WIRES WILL HAVE BATTERY VOLTAGE..usually red, but not necessarily. If you look on the back of MOST keyswitches, they'll be a B, or BATT terminal, and at least that one's hot so you don't need to pull that to test it.

I'd suspect that the voltage regulator, or carb. solenoid is NG both of which are one the same circuit. It could even be the diode in line, which would allow current to try and crank the starter but usually it will crank as soon as you turn the key to "RUN" if it's bad.
The voltage regulator is on the blower housing of the engine, and has 3 wires to it. Disconnect the plug if you suspect it.

Good luck..


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## garfield306 (May 25, 2012)

Thank you, sir, for your reply. Armed with the knowledge you imparted, I searched the wiring from the blower housing back, and found a blown diode. I could not find a voltage regulator.

I showed the wiring schematic to a mechanic, and he said there is no voltage regulator. There is a diode in the line from the stator that "regulates" the voltage ("el cheapo deluxe," in his words). He said replacing the diode would not fix the problem, and I quickly decided that I had no idea how to proceed without blowing money randomly replacing parts. I hauled the tractor to him and will let them try their hand at it. 

If you're curious, the tractor is a Craftsman Model 917.271013 with a CV15S-41567 Kohler Engine. I will let you know what they find.


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## Kenuto (Sep 25, 2014)

So, did they fix it, or haven't you got it back yet?


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