ABS No power on blue wire

[Aero 195]

2003 W900L 899525
No power on the center pin trailer plug (Blue wire).
Trailer 'Hot-line' dash mounted switch will make it hot.
Already checked the trailer ABS relay and 25amp fuse in the fuse panel behind the clutch pedal.

Local KW dealer sent me some wire diagrams but not much help, missing details.

Looked for another in-line fuse somewhere, could not find anything.

Somewhere, somehow, the ABS system powers up this blue wire, trying to figure out how ?

I wish I could locate the circiut (wire) that the 25amp fuse powers up, would really make trouble shooting easier.

Any direction appreciated


Thank You
J.