Right ,
according to Mr Haynes
The Immobiliser antenna has 4 wires
Blue / White A twisted pair ( Yellow / White - Yellow / Brown ) & Green / Black
These run in order L/R to the ZFE pins 57 (55 43) 8
The big problem is that they bring everything into the loom in one big branch under the beak / headstock
I removed
Screen / Kombi / Headlamp / Beak / Tank panel L / Tank panel R / Tank panel top / Tank -
Although you may not need to remove tank top
& moved the ZFE out of the way.
From there i started at the EWS and stripped the wrapping from the loom back to the big branch - nothing found
So then started on the big branch - which is where i found the broken wire -
You may end up going right back to the ZFE, but in reality you wont -
Wires dont break in static areas, they break where they flex or chafe.
the only areas where thay chafe or flex is in the headstock area.
I didnt think it possible myself, but on seeing the break its obvious - your only talking about 1-2mm of movement, but
over the amount of times youve moved the handlebars since 2006 - thats enough
the other way to hone in on an area, is each time you cut a length of harness wrapping away, flex the wires / turn the
handlebars and see if the problem comes and goes
Sounds like your in the home straight its only going to be one of those four wires
also check to see that the cable isnt over tight at the ring antenna,
it could be its pulling the connector apart and giving the failure, althogu id say it was highly unlikley.
( given that you can induce it by flexing the harness)
Edit if the break is in the twisted pair - your need to retwist any cable you replace - theo tothers can just be a straight splice / join )