Battery draining (did diagnosis)

[BlackbirdOfPrey]

My car is drawing about 1.6 A from the battery with everything turned off and shut off. No lights are on or anything. I did a fuse diagnosis, and that got me no where (pulled fuses to look for drain source). The battery was just tested, and is in good shape. Does anyone have any ideas what could be causing the drain?

 

[MNGSX]

Disconnect the alternator charge terminal.. (ring terminal on bolt) maybe the plug too...

It could be a bad regulator in the alt.

 

[luv2rallye]

Are your doors open which turn on the foot lights? Theft alarm or radio memory draw?

To find your small current drain, temporarily and only for testing purposes, connect a small 12 volt light bulb like a automotive tester light, marker light, or license plate light (don't try to start the engine with it in) in series with the positive battery cable. The bulb will limit the current so you now don’t have to worry about any short melting wires. If you don’t have a tester light you may have to solder wires on a bulb or put a bulb in a socket with wires. If there is a short, it will lite brightly (no short may lite it half bright along with a device doing the other half, or it may not lite at all). Then start disconnecting one at a time (1) things that don’t work, (2) suspected things, and (3) anything on that circuit. When you disconnect the item that is causing the short, the light will go out (so it's a great detection device). Keep in mind the short may be in the wiring or fusebox which is harder to find, but first check all the easier, more obvious devices and places.

 

[BlackbirdOfPrey]

I found the drain source. There are 3 fuses on the positive terminal on the battery. I pulled the one labeled MPI (I'm assuming its the ECU fuse) and my draw went to .02 A. When I put the fuse back in it stayed at .02. HOWEVER I let my car sit for 2 days (after driving it a bit) and now the battery is dead again. Nothing on my car was turned on for 2 days, except for my alarm. This prompts 2 questions, could my alarm draw enough juice to drain my battery? Or is the original drain still the culprit? Anyone have any thoughts?

 

[luv2rallye]

The alarm should not drain your battery unless it is defective. 0.02 amps is just the draw for your radio and ECU memorys which is normal. The MPI fuse provides power to the MPI (or MFI) relay which supplies the ECU and most engine sensors, solenoid valves, injectors, and IAC. I'd say the culprit is still there waiting to hit you again.

 

[Forced4]

If your car sits that long at times. ( not that 2 days is long) Just disconnect the battery and reconnect it when you are about to drive it. If the battery is drained you have an internal short in the battery. I have had this problem. Wen you go to have it tested it will test good sometime because when you get there it is charged and will have sufficient power for the load test. I have warranteed many batteries with this problem where I work. Not uncommon.

Rich
Forced 4