Usually if an injector/circuit fault you get a specific DTC for that. 03 Ka had an issue with water ingress into PCM loom and can corrode PCM connector, I had one in at work recently with 3 injector circuit codes because of this. On some build date Ka the dash has to be removed to remove the PCM though.

Ah, Smart charge fault,does the battery light go off then come back on? check the wiring to the 3 pin plug on alternator, remove it, see if it's corroded. or wiring broken to 3 pin plug, there is a repair loom available for Transit Connect 1.8 TDCI that can be adapted for Ka. In some cases the alternator connector itself is corroded and requires alternator to be replaced - which is fun on these as the inlet manifold/front bumper/arches have to be removed to gain access.

There is a fuse on the top side of the fuse box for the smart charge circuit that requires the fuse box to be removed to access.