Hi - interested in hearing from anyone with similar problems. 2003 SL500 - central locking failed back in Feb this year while under warranty (yippee!) - took it to MB dealer who "diagnosed" PSE pump per normal process (ie replace units one after the other until fault disappears) thought that was an end to it. Recently though, it's started blowing fuses. Sequence always the same - unlocks OK, drive off boot locks but door locks don't drop. Remote only operates alarm.

Changed the fuse, all ok for a month, then same again. PSE pump is dry. Water ingress is a pain in these - I've noticed when opening boot after rain that water drips from the trailing end of boot lid (number plate end) right into boot & particularly onto the red switch (that raises the folded roof when needing access to boot) and from there to the boot light.

Pulled the fuse today but boot light still operates, so not a dead short across the light terminals as on different circuit.

Something somewhere is overloading the circuit and it seems it's at the point after the car has been unlocked and as you drive off, the boot/doors should lock automatically, but that might just be coincidence.

Any ideas gratefully received!!