Any updates on this?
Just had a similar thing with mine. Noticed a loud buzzing sound from the rear of the car with keys out of the ignition, left it. Then few days later battery is dead. Checked with a multimeter and its draining 0.37A with everything off! Pinned it down to fuse 21[strike:1w9highb]which is C/L. Thinking the buzzing was the pump struggling to lock or its on its way out. Anything else I should check before changing the pump over?[/strike:1w9highb]
Cheers
Dom
EDIT: Well after having the CL work fine without the fuse in i double checked. Bentley have fuse 21 down as interiior lights/cigarette lighter and rear spoiler adjustment. Thinking it could be the spoiler, but how to check?