Hey guys,

I've been hunting this drain for the past year - I cleaned up my grounds, alternator is new / works great (14+ while running with accessories), replaced the battery back in July, redid my aftermarket radio wiring, etc. But no matter what the battery goes from 12.8v when shut off to 12.3v after a couple days, and to 11v after a week.

I'm reading a draw of ~365mA when the car is off. When I unplug the BTN fuse, it goes down to 220mA. I've isolated this drop to the ROOM Fuse, as no other fuse inside affects voltage. I've checked the dome lights and they're off, ignition key bulb, doors closed, etc.

What I'm wondering is, even when i pull the BTN fuse, 220mA is still a lot - what could be causing this if none of the other fuses (even the ones in the engine bay) seem to affect the current draw?

Any thoughts are helpful - thanks!

 

Update, so if i unplug my alternator, the drain stops lol - guess a diode burnt out... any thoughts on what might cause this so I can avoid it for the future? Should I replace the postive terminal cable with something beefier?

 

Diodes do fail, especially with age in that environment.
I'm not sure theres anything you can do to prevent it beside using better diodes.