I've just bought a 2005 Focus 1.6tdci estate with 79k miles on the clock.

The person I bought it from sold it for spares or repairs as it had been to a garage who said it needs a new diesel particulate filter.

The dash displays "Engine systems failure" and the car is currently in limp mode.

Can I just replace the dpf for a new one and then will the car run normally or does it have to be reset on a diagnostic machine ?