Dead Battery Mystery

[dandeluca]

Went to start the 245 the other day and had a dead battery, which had never happened before even when it has not been driven in a while. I jumped the car took it for a 15 minute drive and it started right back up. Two days later the battery is flat again.

I take the battery into Autozone and after giving the battery a charge they said it tested good.

My multimeter shows no parasitic draw. (well 10ma -- if I turn on an LED dome light I get 150ma) Nothing obvious was left on.

Is there anything known that causes intermittent draw on these?

My next plan is to just leave the battery disconnected for a couple of day and test voltage.

 

[cleanflametrap]

There's a very common and frequently intermittent cause of dead batteries in the central locking feature. The insulation on the wiring to the two lock switches in the driver's door falls off, and the bare wires touch each other, engaging the lock relays and actuators. One night of this is enough to drain the battery. Instead of disconnecting the battery to prove whether Autozone's test was valid, try parking it with fuse 8 removed, assuming you're talking about a 245 year that included central locking and courtesy lamp delay.

 

[dandeluca]

Thanks for the information. This should be easy enough to check.

 

[the_hairy_baboon]

and if fuse 8 doesn't pan out, rinse and repeat with fuses.

It'd be really nice if current data loggers were dirt cheap, especially if they had a couple of loops to sling over suspect cables.