Would it be for the rear brake light pedal switch?
The bike I'm looking at hasn't been touched so the grey plugs go to grey and the white plug goes to white. They are the same type of plug so your prob right. Someone prob plugged them in wrong..Maybe some one connected them wrong on my bike? Maybe both grey plugs go together and the the black is for don't no.
One sec I will go unplug it and see if my bike runs or starts.
Look under hood.Just had a look and there is no other grey plugs round the