Electrical problem?

[jkyle69]

Have an electrical problem with the Tuscan, the headlights and pod lights are pulsing continuously and gets faster when the engine is revving. I popped into a dealership (out and about - 350 miles away from home...) and they recommended changing the main resistor between the alternator and starter motor which I have done and it has not made any difference (although it was easy to do after you took the air box off it was a little bit of a tit about). I am wondering what else it could be? Possibly a dodgy alternator but the voltage does not seem to be fluctuating on the pod display; I was thinking it couldbe a bad earth on the engine block possibly?
One indication which is a bit odd is that when idling the battery light flicks on and very very briefly and this seems to coincide with the pulsing lights although this does not happen when driving along.

Any ideas as I am confused?

[MarkoTVR]

I'm by no means a car electrics expert, but my first guess would be a bad earth too.