Solved the problem.

I had no luck tracking down this code and the dealer wanted to charge me £45 to plug into their machine so I resorted to the old fashioned method.

I tested the voltage to each sensor and all but the left rear were approx 10.5V with the ignition on. The left rear was only showing 0.3v...so something stopping current to the sensor.
After checking at nearby connectors to identify which part of the loom may be at fault I found one of the two feed wires broken where the cable attached to the chassis in the wheel well.

A quick soldering of the broken wire and application of electricians tape (no shrink tube to hand) and fault code removed. Sorted.

Still would like to have known what the code was trying to tell me!

 

Think you answered it in your initial post, nice work with the fix, glad it was simple in the end.

 

The code told you exactly what you found out - bad wiring to the left rear sensor.

Fords machine would have shown that the left rear wheel is doing 999 mph (or something like that) = faulty sensor og wiring/connectors.

BTW how did you measure the voltage - across the tho wires (a probe connected at each) og did you connect one probe to ground on the car and the other to one of the wires.

BTW2 did you feel any loss of power when you had the faulty wiring - some people reported this, but i havent notised it (had the fault two times now).

 

I measured across the two terminals once I had disconnected the lead from the sensor. The voltage was obtained with the ignition on of course!
I had not noticed any difference in the drive of the car (power).