Big 30A fuse melting - 916

[doocatiboy]

Changed belts today (umpteenth time, not a new process to me) and went for a ride. Didn't get far when I smelled plastic burning, turned out to be the large 30A fuse attached to the starter solenoid. Fuse and all wires were previously healthy. The belt change involved only the disconnection of battery, no other electrical manipulation.

Shut it down and the fuse cooled for 5', then switched the key ON and it heated up quickly again.

What's the purpose/function of this fuse? Since, w.it out the starter doesn't turn, I presume it's related to the starter. The bike runs with the fuse out (bypassed the start button and directly jumped the starter).

I can't figure why this suddenly became a problem. Bike has been sitting in the garage since a clean ride 3 weeks ago. What the what?!

[Ben710]

Correct me if I am wrong, but in our Euro spec bikes it´s a 40A fuse. That is if we´re talking about the big bugger right next to the battery near the round starter solenoid.

It´s the main fuse.

[motodave]

Stuck starter solenoid or bad regualtor/rectifier?

[Zillr]

If it is the 30A in the fuse box, that leads to the 7.5A fuse next to it (cooling fan relay, thermoswitch and finally fan), also to the ignition relay and ignition switch. The 40A next to the battery protects the reg/rectifier. R

[Le Kiwi]

All the early Ducati's up to the 996 Biposto had the two-phase alternator and a 30 amp fuse, a big green thing with a clear plastic housing, next to the battery.
If it melts down, your alternator has either come loose and is eating the stator wiring, or the two yellow or the red connectors are dirty, or the regulator has gone on holiday.
All the bikes with the Nippon Denso 3-phase alternator had a 40 amp fuse, a big yellow/brownish colored one, in a sealed black fuse holder in the same place, next to the starter solenoid and battery. Same scenario if that goes "Sputnik !" and starts blowing.

It usually fritzes when there's a problem with the charge circuit, so it shouldn't be too hard to troubleshoot.

[doocatiboy]

Originally Posted by Le Kiwi

All the early Ducati's up to the 996 Biposto had the two-phase alternator and a 30 amp fuse, a big green thing with a clear plastic housing, next to the battery.
If it melts down, your alternator has either come loose and is eating the stator wiring, or the two yellow or the red connectors are dirty, or the regulator has gone on holiday.


It usually fritzes when there's a problem with the charge circuit, so it shouldn't be too hard to troubleshoot.

I've done some research and we have a winna! I'll try swapping regs and cleaning up the wires if they're crusty (though they looked pretty good upon earlier inspection)