Question about 230 E central lock

[johnniebell]

The 90-model 124 central locking system only operates from the rear hatch. When you turn the key in the front door locks, you hear a click somewhere in the engine compartment, but nothing else happens. At some point, the car's alarm system has been disabled. Could this be related to the issue with the central locking?

[EVO X]

There is a cable duct under the carpet in the right rear footwell of the car. There is a rather thick cable in the duct. However, there are several cables inside, and a bundle of red/white and red/yellow cables connected. It is very common for cables to break from that bundle when they oxidize. Reconnect the cables and the door locks will almost certainly start working again.
Other reason might be cutted wires in the driver’s footwell. There is blue/white wire, which opearates the locking, and it’s often cutted when alarm/remote is installed. I recommend to remove all the non original components and wiring from the car and solder all original wires back togrther.
Third reason might be just oxidized connector in the vacuum pump below the rear seat.

[Juhani Halmeenmäki]

In my C124 the fault was precisely in the wire loom in drivers footwell/sill. Extra wires connected to god knows where... I took all extra wires away, and reconnected the original wires, and all good.