On mine it was huge corrosion in a plug above the RH footwell. It wasn’t evident until I disconnected the plug. I don’t recall the plug number, but it was the one that is just a shunting plug that gets a different plug depending on the market.

 

I realize it's been awhile, but can you describe the plug a bit more? Inside the cabin, or under the hood? I'm having similar issues, trying to debug.

 

Inside the cabin. It’s been too long ago to remember exactly which plug, but above the passengers feet somewhere.

 

Thanks for getting back. This helped me narrow my issue to C0287 — the blue connector in black wrap under the glove box. Looks like the Rover engineers saw fit to stick this connector at the lowest point on what would inevitably become a non-draining gutter. This one connector is in terrible shape, surprisingly the others beside it are pretty well intact. Just glad it wasn't the BCU!

 

Glad you found it. It looks terrible!