My LTD DA gets driven once or twice a week. The old battery got flat twice, got a new one from Rpco in May 20012, last Saturday I had a flat battery. The alternator is charging well and the battery holding charge, but something is draining the charge. Would the computer, smart lock, or clock be doing it? (I don't think so) I disconnected the battery terminals and tested continuity / resistance across the terminals, it shows 5.5 on the digital tester. Tested the voltage in the coolant, it shows 0.3V. I think the voltage in the coolant is too high.

If resistance across disconnected battery terminals exists once connected there would be consumption (discharge), I think.

Can anyone tell me if any of this info is telling me anything bad is going on?

Thanks

Anyone?

It could just need a good charge. I own a few cars and obviously can't drive them all at once so the only way to keep batteries, brand new or old, is give them a good charge on a charger for about 4 hours once a month. Otherwise what happens is the acid in the battery always wants to turn to sulphate, the sulphate fouls the plates, this makes it harder to pass charge etc etc. regular charging helps prevent this though the alternator only basically trickle charges the battery, it's not strong enough to clear the sulphate unless it's charged/driven everyday.

Also having said that I drive mine weekly at least 150kms and it's still not enough to keep brand new batteries charged! Still needs a good charge at about 6amps for around 4 hours once every 4 weeks.

And once they do sulphate up, you can kiss them goodbye, no matter how expensive.

Also I would still work on the charged coolant issue because that creates electrolysis which is a different kettle of fish.

Bootlight?

If you're not driving very much then you should think about buying one of those charge and maintain battery chargers.So you just leave it on and keeps the battery charged up until you need to use the car.If it is a calcium battery then you would need a calcium battery charger.Kevman.

I live in an apartment and the car is parked in common underground car park, so, battery charger is out of the question.

I found a dodgy ground connection, I fixed and cleaned all the other ones now the coolant reading is 0.01V. I'm happy with that.

I did some Google and found an amperage test. Disconnect Neg terminal, set the meter to 10 amps. and measure the amperage across the two terminals, it should be 0.05 Amps. I'll do that Tomorrow.

Thanks for reading.

are your interior lights staying on and you have a blown globe so dont notice? same with boot light also?