Good opportunity to blow or brush away some accumulated dust from a unit like mine (5 -6 years service) when the battery is out. Also at this time, used the thin probe tool to ream out some debris from the rim of the base.

The replacement battery cable seemed too long to fit well but when I examined the original, I noted a distinct v kink downwards in that one. A gentle push down in the middle formed a V and permitted the new cable to fit Presumably without harm..