Strange issue. Headlight goes out and abs light comes on

[Martin-Brighton-uk]

Then if I touch the brakes on to put the brake light on, that makes the headlight come back on. Release brake, headlight goes off. This happens intermittently starting today. Now this is the strange thing is, headlight will stay off till i turn the bike off and start back up, then all sweet again. Lights fine, no abs warning. I even did this when moving earlier. Then another issue started coming in. Bike running fine, then would die completely until I turn off kill switch (i have decosse keyless) and then turn back on and restart and then runs again.

 

[Martin-Brighton-uk]

I had the issue before with purple wire to clocks broke and would get clocks stopping working and wouldn't start. Will see if that connection is bad again but this is something else i think.

 

[motolink]

I had some real weird electrical issues earlier this year, the horn did not work, when I pulled in the clutch in the tacho would drop back to zero then start again when I let the clutch out, the motor did run a bit funny now and then. I took the two big electrical connectors of the ECU, found a fair bit of green corrosion in the plugs. Gave the connectors a real good clean. This fixed some of the problems but not all, then I pulled the main harness plug under the tank apart and gave a good clean, this fixed all the problems except sometimes the starter would not throw in,it turned out to be corrosion in the clutch switch, gave a good clean and no more problems at all.
I did put electrical grease on all the connections I pulled apart.
Good luck.

 

[Martin-Brighton-uk]

I had some real weird electrical issues earlier this year, the horn did not work, when I pulled in the clutch in the tacho would drop back to zero then start again when I let the clutch out, the motor did run a bit funny now and then. I took the two big electrical connectors of the ECU, found a fair bit of green corrosion in the plugs. Gave the connectors a real good clean. This fixed some of the problems but not all, then I pulled the main harness plug under the tank apart and gave a good clean, this fixed all the problems except sometimes the starter would not throw in,it turned out to be corrosion in the clutch switch, gave a good clean and no more problems at all.
I did put electrical grease on all the connections I pulled apart.
Good luck.

I'm thinking along these lines too. Going to clean out all the plugs and remake any where I've installed lights and sat nav etc. I've got decosse keyless but that seems to be working okay because when the bike cuts out, the engine stops and the clocks go off, like the kill switch has been pressed, but the red alarm light is still lit, when I press the button to earth the keyless brown wire (I don't use the clutch switch) it powers up and i can start it again. This happened a few times to the point where i can do it when still moving and in fact yesterday while giving a BMW M4 a run for it's money on the A24 (he got past me at this point)

 

[Jay]

Don't know what might be happening, but I can't imagine it is very easy to ride home at night with just the ABS light. It isn't very bright.

 

[DEcosse]

Hi Martin
It definitely sounds like the one channel of the Key-Less is tripping off - when you turn system off and back on again it resets - so that part I understand, at least as far it re-setting with the off/on cycle - however why it should come back on again when you touch the brake is just weird! I can't see any possible explanation for that.(edit - read on!!!!)
As per that circuit tripping - it is only supplying relatively small current to three circuits which explains your headlight and ABS issues at same time (and also actually your running light aka park light - if you were to check that in your fault condition, that should also be off). Any short or excess current on that channel will trip the device (just that channel) and it will NOT come back on, even if short no longer there, until you turn whole thing off and on again (i.e. Kill then Run + new Clutch Pull)
Directly off the Key-Less it feeds into the ABS controller and via fuse # 8 it feeds the enable for the headlight relay and also loops back around through the key-switch connector (not actually into the key-less box, just a loop on the connector) and through fuse 10 to the park lights.
As I'm typing I think I figured it out - I was about to state what possibilities were for the circuit to trip while disregarding for a minute why the headlight comes back on again when you press the brake, when I realized a possible scenario that would cause both the trip AND the apparent re-enable with the brake:
Check the tail light harness under the fender - those wires often rub on the tire and through the insulation exposing the cores; if the running light feed shorted to the ground feed, that would trip the key-less circuit; then when you operate the brake, it shorts to the running light wire and turns the headlight on (important distinction here - this is NOT the key-less channel turning back on that is enabling the headlight, it's the momentary connection from the brake wire touching the running wire and why it goes off again when you release the brake). I could have sworn we already had this issue with you did we not, or am I thinking of someone else? The other possibility could be in the tail light bulb itself (if its incandescent) - I've seen blown/broken filament before touching the other one inside the globe! But I think the harness is more likely, it's far from uncommon problem.
My first thought re the circuit tripping off was that it was another common issue where the headlights have been replaced with LED units, and the park light bulbs are pulled and the sockets actually short out without a bulb in place (Maybe that is the previous issue on yours we had I'm thinking of?) - I was just about to write that first and thought 'OK, but that doesn't explain the brake light thing' and then had a eureka moment (well I hope it is!)
Check out that tail light harness and see if all looks OK there - I would also suspect that fuse 10 could be blown, if your park light is not on 'normal' without applying the brake and prior to the headlights going out.

p.s. I just caught this post by chance - use the @ symbol before my name and I will get a direct alert about the post. e.g. @Martin-Brighton-uk

 

[Martin-Brighton-uk]

Thanks @DEcosse I did replace the rear mudguard with a shorter fibreglass one earlier this year and fitted a (looked to be decent) CE approved LED tail light. It could well be the wiring under there from what you've said. I'll check all those conditions you've mentioned. Yes we've had some fun before a couple of times. Once was the purple wire to my clocks bad connection under the tank. The next one was i had too higher wattage bulbs in the indicator on one side which meant it didn't flash on arm or disarm of keyless. As always the best technical support from you Ken and utmost patience with your user base too (I would be thinking ffs what's he done now). Kudos Sir

 

[DEcosse]

Looks like a cracking day there in old Engurland - just tuned in for the MotoGP from Silverstone - 5am here!!!!
Good luck, hope it's something simple

 

[idk]

Looks like a cracking day there in old Engurland - just tuned in for the MotoGP from Silverstone - 5am here!!!!
Good luck, hope it's something simple

Certainly a cracking day for the cricketers.

 

[Martin-Brighton-uk]

Resolved. It was the custom LED brake/tail light I fitted after putting on short rear mudguard. It was feeding back brake light to tail light or something like that. Anyway replaced with a nice incandescent brake/tail light combo and I'm all good now.