BMW E28 central locking not working
E28 central locking is not working or only partly works – what usually causes it?
The most common cause is an oxidised connector or a broken wire, often in the wiring boot between the door and the body. The door microswitch can also oxidise from moisture. Clean the connectors with contact spray; if a wire is broken, repair it.
Why do the E28 locks lock and then immediately pop back open?
If one door does not lock properly, the other locks return to open. The cause can be a door lock mechanism that has stayed half in the locked position or is stuck. Take the mechanism apart, clean it and grease it. It is also worth checking the control unit's power supply.
Where is the E28 central locking control unit?
It is in the front footwell above the speaker, inside the body, held by a couple of screws. You reach it by removing the speaker and pushing your hand upwards. First check the fuse, the power supply and the door connectors, because the unit is rarely the cause of the fault.