Cant seem to find the cause of blown 15a fuse in my terra Sparky has probed wiring in brake/horn/plate light and headlight but found nothing. No pinched wiring around sprocket cover or oil filter case either It blows fuse at turn of key , no delay I found brake light stuck on one day , caused by bent brake lever , could have been on for hours during trip. Was fine once I bent lever back Another member had same prob but it went away once they fiddled around with wiring at rear. They couldn't pinpoint fault though Any ideas?
Not really. But if its any help, according to the workshop manual there are 2 15A fuses; - Fuse 2 for Horn, Number plate light, Headlight (high beam and low beam), Stop light, Accessories socket - Fuse 3 for Ignition, Injectors, Fuel pump.
Maybe the insulation somewhere along the harness has rubbed off and making contact with the frame. Also, I'd first try disconnecting the horn in case something amiss gone on inside before going the harness route.
You can troubleshoot by disconnecting the parts connected to fuse 2 right and then isolate the problem? Or am I thinking too simple? Removing the brake light switch, headlight connector, rear light, plate light, horn would break the circuit and stop the fuse from blowing right? Then reconnect the things one my one to check where the wiring is bad.
Sparky wants wiring diagram , I've put him on to the workshop manual online but I really need to learn my way around a fault finder myself, Otherwise the bill might be quite large. He's disconnected all the relevant lights/horn one by one , still nothing. The bikes barely been off tarmac , always garage , and completely stock .
How about working this thing backwards....disconnect the entire tail-section electrics, horn and headlight. This will eliminate all of the "users" of the circuit. If the fuse still blows after that, your problem is in the "feed" wiring (core harness), not the "user" part. If the fuse stays good... re-connect one item at a time to see which one makes the fuse blow. Headlight first as they're them major draw....
All the user circuits tested fine so the Sparky opened up loom at rear and above front sprocket and what do you know, the problem disappeared. He thinks these connectors may be causing the fault when enclosed so will insulate them better before closing up. If this doesn't work we may have to pull loom apart further up under fuel tank although his may require tank removal Still a bit of a mystery but at least fuse not blowing ......for now
Great to hear!! And not all that much of a surprise, really. Sounds like standard Italian electrics of the Guzzi/Benelli/Ducati/Cagiva etc kind of yesteryear. It's not so much the BMW wiring harness....but where and how they routed it. Same as the brake-lines/ vent-hoses etc. (bangs head against wall)
All good with Terra , Took it for a long ride , everything working fine. This is where we camp with family for 10 days every Jan. Not a bad view huh.
Great to hear that it's fixed but not as satisfying as if an absolute cause is identified that everyone can check.... oh well.
I am reviving this thread to ask if the fix worked in the long term. I am having the blown 15amp fuse problem...
No the problem continued until I found the wiring harness had rubbed through behind The frame . Hard to see but just trace it back and check each spot where you think it rubs
Just got back yesterday from touring your country for the 4th time!. The South Island (again) is truly magnificent. Thanks for the tips on the harness
