Hi Was intending a ride out on the Thruxton but it’s let me down Key in and no ignition or dash lights, only tail light is lit. Nothing on starter. Checked fuses and the 12V bottom right on pic and Key top left on pic are blown. Replaced them and blown immediately. Tried again with battery disconnected and they blow immediately again as soon as battery is reconnected. Not really sure where to start with this. Hoping someone on here can give a bit of direction Thanks in advance
Looks like there might be a short in the ignition wiring or ignition switch?. Try tracing the wiring from the ignition barrel back to the battery to see if it has been rubbing anywhere and worn through. You could try replacing just the battery fuse, but not the other one, to see if it still blows when you reconnect the battery?
It seems that the 10A fuse protects the ignition switch & starter circuit and the 15A fuse is for the instruments & alarm. You can confirm this in your Owners Handbook. I take it you do not have an alarm?
As above with 2 fuses blowing it could well be the wiring harness. Check around the headstock and also anywhere it could get trapped, e.g under the seat. If you have no luck spotting the problem you could try disconnecting the earth supply to the battery, replacing the fuse then in complete darkness put the battery lead back on and look for a flash where the wire is shorting out.
@TRIPLE X and @littleade , thank you for the replies. I’d found slight damage to the harness covering tape around the headstock on the part that goes to the clocks. I’ve stripped back the tape to inspect the wires underneath and unable as yet to find a bare wire or damaged outer. There was however a burnt electrical smell around the connection to the clocks and this harness. I then replaced fuses, reconnected and everything worked, dash lights, starter, everything. Looked at all wires and moved bars side to side, moved wiring and no issues. Turned it off and on again after another inspection for damaged wire and I’ve now lost the fuel indicator bars but everything else is fine. Next step is to see if wiring diagram in the Haynes manual gives me any clues as to what colour does what. Then it might be to strip back more of the harness tape looking for damage. I’ve progressed but not solved it. Thank you again for your input
Next update…… Stripped back some more of the tape and looked under the tank and couldn’t find any damage. I’ve also moved the harness to different positions within its range of movement while ignition on and can’t replicate the fault. Bearing in mind that the fuel indicator bars illuminate during the ignition on cycle, I wondered if the fuel was just not registering- this happened on the Explorer once and sorted itself out in a few miles. I’ve put everything back on- apart from the new harness tape, been for a quick spin round the block and the fuel indicator bars and miles to go figures woke up and behaved as normal. The bike works exactly as intended with the electrical fault seemingly disappeared! I’m confused because something was definitely wrong but I can’t find the root cause. I’ll tape the harness up before venturing further but I’m going to be worried about it letting me down out on the road.
Agree it's a worry in case it happens again when out and about. Could it be a connector issue rather than a wiring fault? Might be worth disconnecting any relevant connectors (with the battery disconnected) to inspect and clean the pins?
