rather late to the party....
Mate has one of these bikes and his rear ABS sensor had a broken wire, but took dealer a while to think he found it.... But in the end owner worked out what was wrong, by swapping sensor on inputs to the ECU and that moved fault from one end to the other.
Another main thing to remember.... toggle suspension ESA button up for 2 seconds and it turns off traction control and the bike rides normally.
anyway mine was doing the exact fault post originator had and here's my tale of fun.
Something had caused the same module on my k1300 to go mental with
2786 - Front-wheel speed from ABS implausible
if I turn off traction control the bike comes out of horrendous limp mode
dealer finally got a slot to look at this...on my K1300GT built Oct 2009, they agreed front sensor was giving silly reading and swapped it out at £134 for the part, 3 hours later on my way with a new bunch of software on 3 modules, including the engine map...
for 200 yards the new map felt so much smoother... then in 3rd, around 3500 rpm and virtually no throttle, traction control came in. thought no way... was about to turn back thought maybe something on the road keep going.... yep cut in, lights on dash, did a u turn back to the garage and it was almost un-ridable. Tech couldn't believe it went for a ride himself, took back in workshop 3 hours later I'm like what's happening.... he still on it, oh he's got the back wheel out and is playing with something....
Turns out the bike was happy with the readings to operate the ABS "safely" but for the traction control all the bike cared about was each reading both ends made sense and were aligned.... it then sends one signal to the engine ECU to say all good keep going. Except the rear was throwing silly data now and then, which the bike recognised as loss of traction. But as it only receives one signal to engine ECU it just flags the first on the list as a fault... Which is the front even though the back was the one playing up.
In the end I got 2 new sensors, a remap, new central chassis electronics update and new instrument cluster software... under warranty. Rides much nicer now, which is a miracle result as I'd gone 20 miles to drop the bike off and it hadn't missed a beat all the way there, and I thought they were going to say no fault found, go away !!!