Question"I have a John Deere LT155 lawn tractor with Kohler engine
(model CV155). While mowing, the entire wiring harness burned
up. Much of the insulation melted from the wires, even the
ground wires. I suspect that something shorted, possibly due to
mice chewing on the insulation. Before ordering a new wiring
harness I wanted to check if anything else might have gone bad,
or if some defective electrical component was the root cause of
the wiring burning up. By using an ohm meter I see that on the
rectifier/regulator mounted on the side of the engine, one of the
outside terminals (marked AC) is
shorted to the middle (B+) terminal. The normally connected
wires to this rectifier are disconnected when making this
measurement. Is it normal to have these two terminal shorted ?
AnswerThere may be a diode or transistor between the two pins.
If the harness shorted that bad I would replace everything. Key switch, wire harness, battery, battery cables.
I would not suspect any of the safety switches unless there are some special ones. Most of the safety switches should be basic open/close switches but you might want to check with you local JD dealer. We don't get a lot of JD riders in the shop.
Finally, I would remove the flywheel and check the stator and magnets in the flywheel.
The repair will be quite expensive. You may want to look for a donor/junk mower for parts.
Let me know if this helps.
Eric
