Renault clio mk2 not cranking over. Battery reading good voltage. Changed starter motor for new one but same issue. Bench tested old starter and working fine. Noted that when I place jumer cable on negative battery terminal and then to engine to ground it starts not problem. I've taken off the negative battery cable and wire brushed both ends to ensure good contact but still no resolve. I'm at a loss as to what the issue is. My simple mind says it must be a grounding issue? Any idea folks?