Battery drain

I have read that a drain of <0.05 amps is normal, to keep the ecu memory alive (so it doesn't forget codes). The ecu runs off the room fuse. I thought the radio ran off the room fuse as well, but I could be wrong.

Anyway, a drain of 0.07amps is a little bit above what it should be, but I wouldn't have thought it would cause your battery to go flat. It's still a very small drain. 0.07amps x 12 volts = 0.84 watts, which is less than a flashlight bulb.

Then I don't get it. This morning when I tried to crank the engine, fresh-off-the-charger (but still flat) battery started to emit somekind of vapor and neg terminal got a little warm. So I'm prepared to write that battery off as junk. But I have 2 more batteries that I have used before but same problem with now. They can't all fail at the same time!

What could be the reason for 3 different batteries to go flat even though there appears to be no excessive parasitic drain nor alternator failure?

Ahh phuket, I'll try charging one of the batt's 24h and if that doesn't help, just get a new one.

I'd be 100% sure your battery terminals are clean and tight too! may want to get the generic auto part store brass terminals, i've had good luck with them on many cars

So, I added some distilled water to one of the 3 batt's and charged it for about 20h. It's the 2nd morning now and so far every time the car has started like a champ. Let's see how long it can keep it up.