Originally Posted by Broendbjerg
That should be easyly connected at the FRM in the left side of the driver side footwell:
According to WDS it would be Pin 47 on X14261 or Pin 9 on X14260 (either left side or right side reverse lamp. X14260 and X14261 are the two large connectors on the same side of the FRM module.
Hope it works out for you!
This worked, thanks a lot! I used pin 47 on X14261 (the top one) as it was marginally easier to access. It was a purple wire. However, the voltage is not quite 12V so I might have to use a relay and get it from something else (such as OBD pin 1).