Fuel injection problem on 05

I am having my second electrical problem with my 05 ST1300 (57K miles). First one was a bad ground wire in main harness. Fuel Injector fault keeps coming on whenever I ride above 70-75. Engine has a slight roughness when light is on, but still has good power. The flashes indicated the left knock sensor which I replaced. Flashes still indicate the left knock sensor. Wire continuity is good and voltage to sensor is good. Where do I go next? Replace expensive ECM? Buy another knock sensor?

Odds are good the knock sensor you replaced was good, and if you can't conclusively point at the wiring, it's the ECM. There have been some ECMs where the circuit that interfaces the processor to one of the knock sensors has failed.

There's a bunch of useful information in this thread and the others linked in it. Ignore all of the thermostat-related parts.

--Mark

Mark,
Thanks for the input. I have re-cleaned all connections and re-checked continuity of the circuit which is good. It seems to work better when not connected at this point, so I have disconnected. Looking for a used ECM.

Not too long ago I ran into a company that repairs car ECMs. I should see if they can work on the Keihin units in our bikes, because the failure is likely in one of the discrete components on the board and not something that requires programming after replacement like the CPU. As these bikes get older, I'd imagine the failure rate is going to go up.

--Mark

:biker:
I installed a used ECM off of a ST1300P and all is working well again. Turned up 58K last week. Life is good