Main fuse keeps blowing

My 650s (w reg) has decided to keep blowing the main fuse which I mean to be a 15W fuse which looks after the low beam, according to the fuse box panel

When this blows the indicators, rear light/ and dip plus break lights go and I have no displays, the speedo and rev counter falls to zero plus a get no lights on the dash.

I have no wiring additions to this circuit and can't for the life of me think why. Bike is stored in garage and wasn't wet when fuse blew.

Has this happened to any of you before, Is the 15W the right power etc.

Bar tracing alll of the wiring diagram for frayed connections etc I wonder if anyone had the same problem.

Thanks in advance for any tips ideas. Cheers, Justin

[fizzwheel]

Nope but had a simialr one, main fuse blew and bike was totally dead.

Traced to wiring loom chaffing ( sp ) on the frame under the headstock and also by the fuel tank

Have a look around that area, see if its something similar

HTH

[embee]

The other places where the curvy wiring harnesses chafe are behind the 2 rider seat fixing bolts (which are slightly too long, shorten them a bit or add a washer) and under the pillion seat on the left side of the bike towards the rear where the harness goes round a frame bracket before going to the rear light area.

The "main" fuse should be 30Amps, and there is a space for a spare one in the fuse box behind the right frame cover (mine has a green cap). The fuses under the riders seat are the lights etc and are 10 or 15Amps, (Headlights and Signal are 15A, Ignition and Meter are 10A).

Tks fizz/embee,
I'll have a look to see if there's any cables rubbing where you suggest. Correction to the main fuse bit then cos its the 15Afuse under the seat! I'l let you know what I find

I had this exact same problem not long ago altho with the signal fuse
does it blow as soon as the ignition is turned to the on position?

easiest way to find it is process of elimination, try unplugging each item that is on that piece of wiring and replace one at a time. i.e for that fuse it could be,
dimmer switch,
horn button / horn itself (which in my case turned out to be the right choice as it was creating a constant earth thru the fram of the bike)
cooling fan/thermo switch,
speedo pickup (doubtfull but possible) ,
engine coolant temp switch,
side stand switch,
regulator/rectifier.

and last but not least the bulbs them selves (probably the best placce to start ) check for chaffing last as u can be searching forever and it most likely wont be that

hope it all goes well, i know from experience it can be a right pain in the @rse

Tks S1cko,

I've now used up all my supply of 15w fuses but the latest to blow was the indicator. I'll check under the fairing at the headlights, and speeddo pick up as the display did flicker some time ago and intermittently gave up so maybe its a loose connection there. Added to which one instrument bulb needs replacing and taking off the fairing is a long and fiddly task, but I guess now it is time to stop putting it off
tks for the advice I'll tackle it this week end, just when the weather promises to be good I'll be stuck in the garage not out on the bike.

cheers

justin

taking the fairing off is a lot easier and quicker than it seems, i had mine off in about 10-15 mins, the first time i did it.

Hope its something simple and daft like mine!

Apparently the horns a prone to making this problem, as they pick up spray from the road and a constantly heated from the radiator too, so it tends to bugger them up. It took me 4 days to figure out checking the horn as i dismissed early on with it only being a week old, and worked fine when it was first fitted to the bike but as soon as i removed it.. hey presto, no more blown fuses

hope it all goes smoothly and you dont miss much riding time

sd1cko,

I actually replaced the horn with a couple of Fiamms some years ago, and whilst I am on my second set now ( water heat etc kills them), they are wired separately and are fused on their own circuit. However, a good poke around all the wires will reveal something most probably frustration and a fair bit of swearing. No change there then. Still, i'll let you know!!