Ahhh.... at first I read this and believed you did not HAVE a ABS system.
(I do NOT know the specifics re this bike- if it had ABS as an option)
Kobus is totally right.
Check all plugs, wiring and connections!
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This error came after you fitted a new ABS sensor?
If so, start there- Make sure you have the right sensor to sensor wheen distance.
What else did you do prior to the sensor replacement?