So I can quite happily drive for an hour+ with high beams and stereo going. park the car, come back and start it up straight away.

But sometimes my battery just dies. i.e. Go to turn the key and get very little or even nothing (so I jump start), and off I go.

I assumed the alternator was okay and this was a battery issue, so I put in a spare battery which I charged up overnight but it also died.

Have I been playing with 2 dead batteries? Or are these symptoms of something else not working properly?

Check all connections - particularly the earth straps. Undo clean all surfaces and retighten.

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

My mated used to go flat after it sat a while something in the new stereo was draining the battery

It sounds like it is time to get things professionally tested and checked and cut out the guessing.

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DID I MENTION THAT I AM THE BEST SUPPLIER FOR MINI ELECTRICAL PARTS AND REPAIRS?
"Let us remove your "SHORTS"

I agree based on what you have described.

Check if the battery is really flat when you try to re-start it or just not making a good connection up to the starter motor which makes it appear to be flat. If you have a battery charger or some other device for checking battery condition use it on the battery terminals themselves when you get the 'flat battery' condition.

After you jump-start, immediately turn off the ignition and try starting in the normal way without the auxiliary battery. If it starts as normal it almost proves a bad connection somewhere and not a flat battery.

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ex-NSW Police 1970 MK II Cooper S
VMCI #43

Mine had the same so I just brought a new battery and problem solved;-);-)

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when it goes 'dead', check power with multimeter while someones trying to start it. Start at battery, the live side of soliniod, starter side, then bolt on starter. See were power stops. A multimeter is cheap and you can use it for other things.

Battery terminal "scale" is a common problem with any starting issues!
Clean up the battery terminals & connections first.

Cheers Shane

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If it's not a Cooper S, the mini was designed to be modified!

check the terminals on the solenoid also when we picked up latest van one of them was corroded .replaced it and started of the "flat "battery.

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65 panel van Sprog
73 panel van Iggy