Mini 1000 Battery draining - stuartl
I bought a 1991 Mini 1000 three weeks ago which had been sitting for a while.
No problems for the first 10 days then flat battery one morning.
Charged battery and it started fine. Switched off engine, went to restart and the battery was dead.
Bought new battery, fine. Few days later, went to start car and the battery was dead. Jump started, let run, drove for a mile or two, switched off, went to restart battery dead again. The ignition light comes on wen you turn the key and once the car has been (jump) started there is no ignition light on to indicate a charging problem.

Could it still be an alternator fault even though we have no ignition light showing?

Many Thanks in advance,


PS I have removed the bulb from the interior light so I know its not that, there is no radio or other extras fitted apart from an alarm which is never used.
Mini 1000 Battery draining - ChrisMo
I had a similar problem with a mini, turned out to be the earth strap from engine to body was frayed (then broke completely!). It was a while ago, but as far as I can remember it runs from engine to bulkhead near the stabilising bar that stops the engine rocking backwards and forwards.
Symptoms were battery wouldn't stay charged and very slow starting, ran fine once push started.

Mini 1000 Battery draining - George Porge
Check the bulb on the dash is ok as it "excites" the alternator into opperation. Also check the wiring from the alternator to the bulb ;o)
Mini 1000 Battery draining - domcr
Stuart, suggest you charge the battery until its full, make sure the car will start ok. Then disconnect the battery and pull the plug of the back of the alternator and reconect the battery. Leave it for a day, disconnect the battery and reconnect the alternator, then the battery. If the car starts then the alternator is at fault. If the battery is drained then its something else ? my suggestion would be to disconnect the radio next. You only have a couple of components with supply when the ignition is off, radio, hazzards, supply to the alternator ? so its just a case of elimination.

Ohh ? what ever you do don?t try to start the car with the alternator disconnected!

Mini 1000 Battery draining - Peter D
Get the car up and running and drive a couple of miles or so leave ar idle and measure the voltage across the battery should be 14.25 volts ish with no load. I am ssumming you have a meter. IF so then loosen the + terminal Engine off and place the meter on the 1 amp scale between the battery terminal and the lead, this current should assuming no alarm and radio off etc etc be micro amps, however if the diode back has a fialed diode this can be the cause of the drain on the battery. disconnect the alt and measure it again. if now zero then you have the problem. Regards Peter
Mini 1000 Battery draining - stuartl
Thanks chaps, some interesting things to try

>>>>>>my suggestion would be to disconnect the radio next.

It doesn't have one, almost everything is an extra on an old Mini!!!
Mini 1000 Battery draining - Screwloose
Charged battery and it started fine. Switched off engine, went to
restart and the battery was dead.

If the battery was fully charged, it can't drain in that space of time. A dead cell could [just] have done that, but the new battery does the same, so....

I'd go for a poor connexion on the battery terminals, either end of the boot earthstrap, the solenoid terminals or the previously mentioned engine strap. If it's the engine strap, the headlights won't dim when it's cranked.

>>Jump started, let run, drove for
a mile or two, switched off, went to restart battery dead.

A very flat battery may need hours of driving before it's recharged enough to start the car. They can be very reluctant to take any sort of charge.

Mini 1000 Battery draining - Pugugly {P}
Is the Alarm draining it even wehn inactive ? If this is an aftermarket one (which probably is) that may be earthing out somewhere and draining. Otherwise it's reading the "fault codes" described above. My money would be on the dodgy earth straps, How old is the battery ?
Mini 1000 Battery draining - Pugugly {P}
Sorry just read the OP on the new battery (doh)
Mini 1000 Battery draining - stuartl
I've checked the earth straps and all looks good. I verified this by running a jump lead from the neg battery terminal to the engine but no joy. Think i'll remove the alarm anyway, trickle charge and try all the above tips.
Mini 1000 Battery draining - the original horse
remove a working bulb from the car , blow over the top of the battery, disconnect the negative - [earth] terminal from battery , and put the bulb across , with everything turned off it shouldnt glow, if it does then somethings shorting.
bear in mind new batterys can also be faulty .
Mini 1000 Battery draining - kithmo
If it's the same as the original Mini with the battery in the boot, check underneath the car, the main positive battery lead runs the full length of the car and is susceptible to damage. If the car has bottomed out on a kerb or ran over a large object in the road etc. the cable gets frayed and shorts out onto the body.
Mini 1000 Battery draining - kithmo
Just remembered another one, the battery had a cover on and if left off, any large metal tools (e.g. jack handle) in the boot could fall across the terminals and short out the battery (have seen a few exploded batteries on minis).
Mini 1000 Battery draining - dan_b
it could b something as simple as a loose alternator belt so it isn't chargin the battery or it could b a dodgey alternator it'self or it could b that the alarm is not wired in properly so it is shortin out and dischargin the battery

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