Finally decided to hook up my VOM and find where my battery drain is coming from.

Its a fuse to the left of the dash..I think it's called IOD?? So, now that I know it's that circuit,..I don't know what to do after that.? Gee,...on a car...I would have no idea on how to test a sub-circuit...unless someone had an awfully good wiring diagram.

How many things are on that circuit??? In the meantime,..I'll just keep that fuse pulled unless I'm going somewhere. It draws around 450 to 500 milliamps unless I pull that fuse,..then it's like...10 or 20 milliamps.

 

I was looking at my wiring diagram and didn't see anything called IOD. The diagrams call out location numbers, is there one for that fuse?

 

The IOD "ignition off draw" fuse is designed so that the dealer can pull that fuse while the vehicle is sitting on the lot or in the show room and not kill the battery. Things that need power all the time are on it, like the radio memory for example. It has the yellow case over it so it is easily recognizable. Try disconnecting the under hood light, I leave mine disconnected all the time then just plug it in if I need it, the switches go bad after time and the light remains on when the hood is closed, also check the glove box light.

 

There is a timing module that unlocks the seatbelts on a quad cab (by powering the solenoids) and keeps them unlocked for a few minutes after the door is opened or key turned off. Some go bad or have a false input and will leave the seatbelts unlocked full time. Easy check is to pull the key out of ignition, leave windows down and after half hour the seatbelts should be locked. Amp draw on the IOD should go down too I believe. If they never lock up, that is your drain.

Glove box light or aftermarket radio are other common culprits.

 

I did think of the seat belt module but the amperage draw didn't seem like enough to power the solenoids, it wouldn't hurt to check that though.