Not T3 (VW Caddy)

[R0B]

My mate's 2006 Caddy drains the battery when left overnight. One "expert" told him it was a duff battery. He replaced it with no change. Another "expert" with a laptop diagnostic tool told him it was a duff alternator. He had a new one fitted. No change. I (No expert) suggested he should remove the central locking fuse. The battery didn't drain. So we now know the problem. But where to go from here?

[davidoft1]

Unplug all the units , plug one in at a time until you get a drain or something makes a noise, also check the rear door latches are fully locking as they have a tendency to get stuck leaving the rear light on

[R0B]

Cheers David. I will inform him.