i have recently bought a 92 sl 300 r129 and find this forum fascinating and i wonder if any one can help me? i only got the valet key with the car so i will need to get a key from a dealer i would like to test the vacuum pump first but dont know how to do it . the manual locking switch on the door locks the door but doesnt opperate the central locking . if i need a key, receiver and pump am i looking at a hefty bill? a local auto electrician says he can fit a remote alarm to operate the central locking for £300 but the vacuum pump needs to be working anyone any advice?