So I've got a 300Tdi, last week the central locking failed. Actuator is making sounds when I operate the lock, fuses are OK and I have voltage at the actuator connector (12.8v). Bought a brand new actuator so I know it's not that. I don't have immobiliser or alarm, so don't have an ECU controlling central locking, RAVE states that central locking in my model disco (98) is controlled by RHF door actuator. All door locks operate fine independently and door locks with key on RHF and LHF door, so doesn't look like spring. One thing that I've noticed is that the 15amp fuse on satellite 2 of the fuseboard has blown a few times, but that's the only thing that points to an issue. Has anyone experienced this kind of problem before? I've not checked the spring physically but it doesn't seem like a spring issue, can anyone lend any insight pls?

Sometimes aftermarket actuators are not strong enough to operate the often stiff locks on old discos.

Start by disconnecting actuators from all faulty doors and see if they will operate with no load. If they have a decent amount of push pull when operating then you could assume they are working nut perhaps not strong enough.

Check all linkage etc.

Door lock springs cause faults with tired actuators because they make it quite difficult for the actuator to lock and unlock the mechanism.

Chrrrs