I've a problem with a truck failing to start after 5 days sitting idle - completely flat batteries, no ignition lights, no "click-click-click", nothing.
The electrical sytem is supplied by 2 x 12V batteries. These are 21 plate,
800 CCA big lead acid units, each larger than a large 4WD battery. The charging system works fine with over 28V at fast idle, and around 26 at idle. It starts fine after a couple of days sitting idle.I've measured the standby current draw from the batteries with everything switched off at around 150mA. As far as I can tell the standby current mainly goes into the remote entry system and a 24/12V converter.
From my rough reckoning, 5 days @ 150mA = 120 x 0.15 = 18A.hr which should have bugger all effect on such large batteries.
Comments or suggestions???
Thanks.