Hey Callum what brand was the elec unit that failed ? just a thought but are you sure it failed or could it have been the "overheat" protection circuit in your battery that cut the power (do you know what the "re-set" time is for this ?)
I'd rather not say which brand it was as the guy usually does a pretty good job and I don't want to bad-mouth him here...
The unit definitely failed. I have a new replacement unit on the shelf.
