The BMW 518 central locking relay switch is located beneath the dashboard. The central locking relay switch will be on the drivers side of the dashboard.
The central locking relay is attached to the ECU, fitted behind the right (EU) back passenger side panel.
negative triggering relay.
drivers side door
They are at the back behind the ashtray, look in the gap at the top of the fuses.
There are 4 central locking relays on this car. In one of the engine bay fuse boxes, the one whcih contains the multi fuction module. There are six slots above this, 4 of them contain the central locking relays. Good luck....
inside of the driver side door
in the fuse box under the bonnet its a 15amp blue.
If the car has an alarm system or remote locking (Key fob) the locking control box is behind the side trim in the (UK) passenger footwell, if there is no alarm there is no relay box the system works off the door being locked and it sends a lock command to the other door
Vectra B Switch ignition on programming mode active for 30 seconds press lock or unlock button Central locking system operates to indicate confirmation New keys can only be programmed by using diagnostic equipment.
Two wire connection in the fob. Open and check both wires are fix in place.
Central locking on madza 2 not working