blowing brake light fuse 94 m600

[roofrat]

every time I apply the brake lever front or back I blow the fuse the horn is on the same circuit but sounding that doesn't blow the fuse got mot this week any ideas

[rollo22]

Try looking at wires under "T" tray.

[Martin C]

Also, remove the rear light lens and expect to find lots of rusted contacts in the fitting in need of thoroughly cleaning-up. These increase resistance in the circuit, consequently more current flows when the brake-light switch is operated and when the current exceeds the fuse rating it blows the fuse. Do NOT just fit a higher rating fuse to "solve" the problem!! Fires caused by overloaded wiring circuits can be quite nasty.....

[roofrat]

found the problem shorting out under the seat locking mechanism thanks for the help roofrat

[Dennis menace]

To quote Jay Leno in The World's Best Motorbike Rides:

"Anyone who can fix Ducati wiring is a genius."

[Islander]

Also, remove the rear light lens and expect to find lots of rusted contacts in the fitting in need of thoroughly cleaning-up. These increase resistance in the circuit, consequently more current flows when the brake-light switch is operated and when the current exceeds the fuse rating it blows the fuse. Do NOT just fit a higher rating fuse to "solve" the problem!! Fires caused by overloaded wiring circuits can be quite nasty.....

Eh?

Sorry but increased resistance = lower current draw. Simple Ohm's law I = V/R

In the example of the rear light given, corroded contacts will lead to the light being dimmer than normal or just not working. A clean up and a dod of dielectric grease will sort that out.

Fuse blowing is usually the result of lowered resistance somewhere in the cabling - if it's blowing instantly then a short circuit i.e. zero or close to zero resistance. Of course, fuses can also become 'tired' over time and fail for no other reason.

Good point on the fuse rating though. Fuses are there to protect the wiring and to stop dangerous overheating.