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Utopian2
,
11 April 2024 - 06:19 PM
I'm sorry to say that people might not learn much, and it's a bit embarassing, but here goes.
I spent the last two evenings reading up on the electrical side of things.
As part of this it was mentioned that you should always check your multimeter before each use, I hadn't does this for a few years (that's Lexus for you...), and they had always checked out fine.
When touching the points together, I got a figure of around 0.5 Ohms - rather than zero or near-zero and not far off the reading when testing each fuse.
I also read about 'Phantom Draw' (or 'Drain'), which suggested that the battery may have been constantly running down all the time I was trying everything else (again the duff multimeter not helping much).
So, as a last attempt before sending it to the Mini specialist, I thought I'd take the battery out and charge it in the house, to keep an eye on how discharged it was.
It took 10 hours to fully charge a bog-standard ~40AH Halford's battery, obviously meaning that it was completely flat (6 Amp (rms) charge).
Anyway, so I put the charged battery in and tried the car this afternoon - the lights etc worked, which suggested it wasn't as bust as I had assumed, but still no cranking.
I figured that just replacing every fuse & the battery would be a small fraction of a tow away and repair, so I got a lift to the little side street car parts place, bought the specified bag full of fuses and a Yuasa 075 Battery with a 4 Year Warranty (from GSF).
I unscientifically replaced all the fuses in the car and it started first time, on the 'original' battery!
So, a big thanks to 'KernowCooper' for his encyclopaedic knowledge of the Mini's electrical system, and electrics in general.
Although the old battery was able to start the car, KernowCooper states that a battery once completely flattened, it isn't worth having, so I think I'll put the Yuasa 3000 075 one in it's place - £69 from GSF as a 'click and collect' price seemed ok, and ups the capacity by a third to 60AH.
But it was the fuses that did it - for £10!
I'm only sorry I can't add much to the pool of knowledge, without having identified the specific fuse causing the fault - but at the price, who cares really.
Thanks everyone, and good luck to you all.
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