2014 Thruxton Efi Canbus Issue

Evening all,

I'm new here but hoping that someone somewhere might be able to help?

I'm hitting my head against a brick wall with a supposed CANBUS issue which seems to be stopping the bike starting. TuneECU reliably reports code P1690, even after clearing. The engine willl crank fine but I never hear the fuel pump prime on turning the ignition. I have however successfully tested the fuel pump via TuneECU and it seems to work fine.

I've had it up off the stand, given it a bit of a shake, clutch in etc...nothing seems to help but again I can't see this making any difference if the fuel pump isn't priming prior to cranking as it usually would.

I've checked the Haynes wiring diagram and chased the blue and red wires from ECU to speedo and rev clocks. Continuity tests are reporting everything is looking great with sub 2 ohms readings on everything. So I decided to remove the headlight and fuel tank and check for anything interesting that might be screwing with the circuitry. All wiring looks in good nick with no signs of damage. The wire split connections to the clocks look in great shape.

I'm now considering whether the ECU or one of the clocks are busted in some way. I could send off the ECU to Carmo for a full diag but of course I don't know if it's that or one of the clocks.

I wonder if there's any way to be sure? Both are sealed units so I'm not quite so sure where to start but again, no signs of damage on any of the units. Or the ECU.

The only thing I can offer in addition is that whilst the speedo/rev counter does it's usual dial initialisation, I note that the engine management light doesn't come on, even though P1690 is reliably flagged. Yet it shows as being illuminated in TuneECU along with the neutral sensor. I'm not experienced with TuneECU so I don't know if this is a red herring or not but it's the only other observation I have left before I swallow the £60 charge to send the ECU to Carmo.

Any guidance anyone can offer at this stage would be hugely appreciated.

Cheers,

Steve