Strange issue. Headlight goes out and abs light comes on

I hear what you're saying Ken @DEcosse, it is very strange. I will look at the wiring loom from the headlamps back to see if there is anything causing some short. I will get further information when the issue occurs too, like when the issue is present, are brake/tail/ park/full beam headlights/Horn/Indicators work or coming on when either front / rear brake pulled.

Meanwhile, if I want to put in a switch so I don't have issue if I am on a ride, according to some other posts, Ignition wiring bypass diagram.
I can just put a SPST toggle switch on the white/blue wire switching it to the Green and Blue/Yellow. The RO and RU I can connect together and leave the orange wires disconnected.

Thanks for the help and patience too

I would try to disconnect the keyless system and reconnect the ignition switch if at all possible to rule out any issues with the keyless module. Sounds like an intermittent issue that could be a bad ground, intermittent short or failing component. The solid state devices that Ken uses are not prone to failure like old school relays, but anything is possible. More then anything, it would rule out Ken's system and it's associated wiring. Then if it continues to happen, you can focus on wiring/components on the bike itself.

Thanks @Stillserving. Yeah I was thinking along those lines. I had to disconnect the keyless when I took it in for custom tuning as the mechanic said it was interfering with the pickup he was putting on the coil. Unfortunately the ignition switch part can't just be mounted back onto the keyswitch part as it was damaged getting it out, but I can use it as a switch still.

Martin - can you possibly swap the Blue And Orange Wires on the power connector (or the corresponding ones opposite on the main harness connector)
I know those terminals can be a real problem to get out however - the females on the main harness side tend to be a bit easier - either way you first need to remove the orange retainer.
The object is to swap those two circuits, whether you do on the main harness side or the keyless harness side
Blue = Lighting output
Orange - Brake/Turns/Horn output
By doing that we swap over the outputs for each circuit to a different power switch - we can then see if the problem follows the switch channel output or the same device still trips
i.e. the Lighting will now be from the third output channel, the orange one and the brake/turns/horn would be from the second channel, the blue one.

You could also try connecting the lighting circuit to the orange output - there is a really low current load on the blue circuit from the keyless on a Roadster - it only supplies the park lights, the ABS module and the Lighting Relay*
* It also feeds the accessory connectors for accessory lights and clock - do you have anything connected to those OEM connectors?

- let me think for a few mins about how we can make a simple link between the circuits without having to pull those terminals - pulling Fuse #8 isolates all of those circuits EXCEPT the ABS - so the idea would be to pull Fuse 8 and then connect the downstream side of Fuse 8 to the Brake/Turns/Horn circuit**

Just a quick refresher for me - do you have anything else connected electrically to your bike? Anything at all, even if you think can't be related, just so I get a full outlook on things
Are either of the harnesses from the keyless box running close to anything that could be generating some EMI? Not close to the coils or HT leads or anything like that?
(can you remind me - does your kit have extended harnesses with box located in the old airbox?)

** can you possibly make up a small jumper wire Martin with a male terminal on one end a - what you could do is pull the Horn Positive - that would be the Black/Blue one - and insert one end of your wire with the terminal onto that; then pull fuse #8 and put the other end of that wire into the side of the fuse 8 socket that has the Red/Blue wire on it with an appropriately sized terminal that fits the fuse blade size - alternatively you can pull also pull fuse 10 - strip the end of your wire and put it in the fuse 10 position - either side does not matter - and replace fuse 10 fuse to make the connection with the wire and hold it in the socket
What this will do is make the Blue Output ONLY feeding the ABS; the Orange Output will now supply the lighting and accessory sockets as well as the original Brake and Turns. We can the see what happens - does the Orange circuit now trip? If it does, suggests some influence from the bike is causing that.

Hmm, now saying that, I had the other week an issue where the indicators stopped working, but the headlight/rear light and ABS were still working but it's mostly the issue where the headlight/ABS goes out. I wouldn't be surprised if something like a dodgy coil/reg-rec is tripping it.

It was interesting when I took the bike in to go on a dyno a while back, he had the bike on a Dynapro load cell but said he could only get to just over 5.5k revs before his PC crashed out. He said it was caused by where he had the pickup connected on one of the coils and it kept crashing it out.

Thinking about it, this is when the issue often gets triggered on my bike, when accelerating hard, it trips. But not all the time, sometimes when on mid throttle too. Yes I have the kit with the extended harness and it is located in the airbox (which is completely dry not filled with water). I will try to move the loom away from the HT leads. Hmm.. another thing I had previously was two HT leads that had broken down inside. I only found that issue when I was swapping coils and HT leads as there was a separate issue of misfiring.

The issue's you've resolved for me so far as where I had 21w indicator bulbs in and it wouldn't flash when arming or disarming. Also the range of the remote was really short and I found the antenna had some off, you sent me a new one and I fitted that to the keyless, oh and the patience with me while I've got my fettling head on..

Martin

That's interesting info on the coils issue that your tuner experienced also (maybe try the stick coils mod )

I had another UK user - just up the road in Guildford - with a Thruxton, and the EMI emitted from the Stator harness was tripping his - simple relocate of the Stator Harness/R/R resolved that.

Try routing the power harness down the left side of the frame Martin - you can probably keep the alarm connector harness on the right side, but try to move the actual connector/main harness directed towards the rear of the bike as far as it will go, thus keeping that as far from the HT side of things.
May not be it, but good to at least minimize any effect from that

I've moved the keyless loom now to run along the air intake side of the bike. It was quite well intertwined around the coils and HT side of things. Before picture attached. Forgot to take after picture before putting tank back..
I'll see how it goes Ken.

So, issue still occurs but guess what.. now the headlight does not come on when I use the brake when the circuit has tripped.

Maybe the interplay between the headlight circuit and the brake light is now cleared where I rewired the all the back lighting.

However I do still get that lighting circuit tripping out. So I am now going to follow your instruction to swap the Brake/Indicators/Horn circuit and the Headlight/Sidelight/ABS circuits on the keyless by swapping those wires in the plug.

Interesting fault finding, thanks for your patience Ken. And for what it is worth, I don't think it is the keyless.. I have faith my friend that your electrics are better than the stock wiring after a few years + my little modifications.

I might also leave it plugged into the battery tender and leave the bike powered but engine not running for an hour or so.. see if it trips out??

All the best, Martin

One more wonderance tho.. If something like a short or over current occured on the lighting circuit, would it trip the circuit that runs the engine? I get that too sometimes, that rather than the lights tripping, the engine cuts out and it goes back to red-alarm-symbol lit stage but I have to power off the bike via kill switch, then ground the brown wire to get the unit to power up the bike again.

Martin-Brighton-uk said:

Maybe the interplay between the headlight circuit and the brake light is now cleared where I rewired the all the back lighting.

Click to expand...

That could only have come from short across the circuits Martin so I suspect you are right there and have removed that issue. I wonder if the power switch has become overly sensitive to tripping after the brake/tail light wiring issues?

The lighting and the ignition switches both come off a common power feed to the inputs of those switches; any power surge or EMI could potentially be transferred from that common source.
the brake/turns/horn switch has an independent input supply;
that's why I suggest if you can swap the lighting and ancillary outputs, we can get the lighting on a fully independent circuit; that way we get some good data - if lighting still trips, it's being triggered by some load influence on that circuit; if the brake/turns/horn trips instead, it's potentially the #2 power switch circuit in the box.
(as I say, you can actually just put lighting AND Brake/turns/horn circuits off the same switch - in this case we would want to transfer the lighting circuit to operate off switch 3 along with those ancillary circuits - you're adding very little current to that power circuit - it might be easier to accomplish, especially for testing, if you can jumper as I had outlined earlier (without swapping the terminals which as I say is a bit of a royal pain on these connectors)