Over night battery drain

[Robmills72]

A few weeks ago my 4runner went for a swim. The truck went in nose first and I stopped it but it was already too late, water came in the door jambs (just the front near the dash)I've already gone through 2 batteries and they drain literally over night just sitting. No lights or switches left on, no trying to start and it still kills the battery in a matter of hours. Is there something that is known to short or stick a relay or should I just start looking into all the relays etc?

 

[KidVermicious]

You've got what's called a parasitic drain. Get out your multimeter and stick it between the positive battery stud and the positive cable terminal and you'll see it (make sure all the doors are closed and the key is off, obviously, you don't want to chase your dome lamp). You isolate it by yanking fuses until it goes away, then you'll know what circuit to troubleshoot. If you went for a swim, it could be more than one circuit, so be persistent.