my battery keeps draining completely every 2 days. i replaced the battery. i took the alternator out to get tested and it came back good. i have nothing on in my vehicle when the motor is off. i have no clue why the battery is draining like this. what could possibly be the problem?
battery problems on 1996 Ford Explorer
in order to find what's drawing on your battery you need 1 small piece of wire (or a close hanger) and a light bulb that you can get from your turn signal or dome light. take off your negative battery cable. put a wire from one side of of the bulb to the battery and the other side to the battery cable. you may need to tape them on. the light will probably light up. touch a 3rd piece of wire from the battery terminal directly to the cable end. the light will probably go off. remove the last wire & if the light stays on you have parasitic draw killing your battery. you can make sure the system works by opening your door to make sure the light comes on. pull fuses until the light goes out. whenever the light goes out you found the circuit with draw. find out what doesn't work with the fuse out & you know whats on the circuit. one of these things is killing your battery.
i tried the light bulb thing and i couldnt get a steady strong charge to the light. the light would just flicker. i had to dab the wire onto the negative terminal to keep getting a strong charge to the light. and i pulled all the fuses 1 by 1 and the light never went out. is there any other way. i was reading something else and they said to use a volt meter instead of a light bulb. would that work better?
if you have a voltmeter that reads in milliamps you can connect it in the same way as the light bulb to check for draw. after you remove the 3rd piece of wire that bypasses the meter (or light bulb)it well tell you what the draw is in milliamps. a few hundred or less is acceptable. if you have any more then pull fuses until it goes away (you may have 2-3 fuse boxes). in order to use the amp function on voltmeters you have to change the common lead to a different hole, don't forget to put it back to test voltage or you will blow the fuse in your meter (cost me $5 every time i forget). if there is no draw then check your charging, battery negative to alternator positive terminal should be at least 14 volts, check the same in ac volts to check for ripple, should be 200mv or less. cleaning your batter terminals & cable ends could help but its a long shot.
i finally found the problem. i went out and bought a circuit tester with a bulb in it and the jbl system fuse is what was drawing the power from my battery. i have no sound from my radio right now but thats ok for now. that was the only fuse that the bulb went out on me. so i took it out and hopefully my battery wont drain anymore. thanks a lot for all the information you gave me. it really helped and saved me a LOT of money. thanks a lot
3 answers 3 comments
The same thing happened to me this week with my '96 Explorer . Battery light came on, would not go off. But my amp meter is showing that my alternator is doing its job. I left the lift gate open for about 2 hrs and when I went to start it the battery would not turn the engine over. Jumped it and didn't have a problem...but that battery light was still on. If the serpentine were slipping enough to cause the battery light to stay on it would also be squealing non-stop, so I never thought that. I disconnected the negative battery cable and drove it for about 4 miles with no problems, I figured the alternator was not the problem. Installed a new battery from another vehicle, battery light still stayed on. I then got a piece of scotch brite and die-electric grease and disconnected every ground wire and strap I could find including batt cables. Battery light still on. I then had my son sit in the drivers seat and instructed him to let me know if/when the battery light flickered. With the truck running I started wiggling wires and connectors, when I got to the back of the alternator he told me it blinked. I shut it off, disconnected the neg battery cable, popped the connectors off the back of the alternator cleaned and greased all the connectors. Started the truck the battery light was off and has stayed off.
I had identical problem on '96 EXPLORER. If I let the car sit for more than two days the battery went dead. I used to disconnect the battery if I did not plan on driving the next day. I tried replacing batteries, alternator, etc with no effect. I left the car with a auto electrical specialist and he determined there was a current draw from the sub-woofer in the sound system even with the key off. I had the radio completely disconnected and the problem went away