@Salieri It was the same with the Land Rover Discovery. I think the modern electronics vs battery technology require some clever stuff that they don't want customers to get anywhere near. Anyway, 20 mins with an old fashioned charger has got me up to 12 V and I'm leaving it on the semi-smart charger. At least I know how it works now.
This has been an interesting exercise ! After leaving the battery isolated last night, it lost 0.5V, so I gave it 4 hours on the smart charger and it went up to 12.8V. I know I should have left it longer but I've been home since Thursday and quite miss driving the little beastie so I reconnected it. The car started on the first turn and, although the remote wouldn't open the doors, it did sort the immobiliser. Then I set off for an hour of mostly motorway with a few miles of the country back roads. After the remote problem, I thought I'd chance the windows. Rather gingerly, I lowered the passenger side and it refused to come up. Being a sucker for punishment, I got the same result with the drivers side. My cigarette lighter voltmeter was showing a steady 14.2V from the start so I left it a few minutes and lo, the windows started playing nice again. When I got home I tried the boot - all good, and the remote started playing nicely again. I haven't been brave enough to try the roof yet but will get around to it if everything stays settled. Engine off, the voltage dropped and steadied at 12.8V so I'll watch it for a couple of days and see what happens. I've ordered a multimeter to see if there's a vampire draw. Fingers crossed, the battery isn't toast but I've found an Optima for £50ish on the interweb. Thanks to all who contributed to the thread.
