Just collected my 2003 1150 Adv from Scrimingers after having a custom geartbox fitted. Unfortunately by trailer - hey ho...
Got back to my mate Peter's garage and decided to fit the HIDs and Autoswitch I'd bought. Bike on ramp, tank off, headlights off. Decided to sort the autoswitch first, so disconnected the right hand handlebar switch main plug under the tank, before baring a section of the Brown/White wire on the 'bike' end of the connector. This is the 'Turn Signal Cancel' wire and should give a pulse to earth when the indicator cancel button is pressed.
Reconnected the plug and put the multimeter on the positive battery terminal and the bared wire, turned the ignition on - no reading. Pushed the cancel button - once again no reading. Hmmm. Tried the Turn Signals - they didn't work. Checked that the plug was correctly seated and all pins in good condition. Neither indicator worked.
Weirdly, though, the hazard lights worked as advertised from the switch, both on and off.
Work I have done affecting the Turn Signals recently:
Fitted rear LED Turn Signals with extra brake lamp LEDs - these worked as advertised after fitting and the brake light LEDs still work - as do the Turn Signals, but ony as hazards.
Fitted front LED Turn Signal and these also worked as advertised (and still do - but only as hazard lights).
I rode the bike 70ish miles to Sleaford last Saturday when all the Turn Signals were working OK. Steve Scriminger replaced the gearbox, the header studs in the heads, changed the final drive oil, fitted a new clutch slave cylinder and air filter. He also did a throttle body balance. None of this would, on the face of it, have any effect on the problem - I mention it for completeness.
I have a spare Turn Signal relay in the garage somewhere, so I'll be replacing that as a logical next step, but I'm pretty sure the same relay controls the hazard lights, so I'm not hopeful that this is the cause.