My first post here, plus I'm relatively green wrt Mini's, so please be gentle!
Our 1998 cooper is suffering apparent electrical gremlins. If left for more than a couple of days the battery is quite often flat - not necessarily completely drained but enough to require a push or jump start. The engine fan also rarely turns itself off after it has first kicked in when the engine is running.
I know the alternator is OK - the instrument volt meter reads between 13 & 15 when the engine is running and having had a multimeter across the battery when running I know it is giving a voltage of about 13.7. The battery itself is also less than 6 months old.
The earth lead from the battery to boot floor is in good nick and there seems to be a good connection there.
We have had a local autoelectrician, who specialises in Rovers, look at it and they reckon that their are no faulty circuits that might otherwise cause a battery drain. Their only suggestion is that the CPU/ECU is faulty and are suggesting that we replace that. Of course this is relatively expensive.
In trying to source a 'pre-loved'(!) ECU I spoke to a mini specialist oop north who suggested it might be a fault with the 'ballast resistor'. Having done a bit of googling I think I understand what a ballast resistor is and what it does but I don't really see why a faulty one would cause the faults we have been experiencing. I have also completely failed to identify anything under the bonnet that looks even vaguely like the pictures I have seen of these ballast resistors.
Does anyone recognise these battery issues as a known fault and/or give an opinion on whether the ballast resistor idea has any merit over the faulty CPU theory?
Cheers!
Edited by CDubya, 11 September 2008 - 09:01 PM.
