I cannot figure out why my battery is draining on my 96 4Runner. If I leave my car sitting for a straight 24 hours, she won't start without a jump. Obviously there is a slow drain somewhere. The dealership and Autozone disagree about needing a new alternator. I figured it wouldn't be an alt problem if this was happening with the car off. I have

1)cleaned the terminals
2)tested voltage across fuse terminals
3)tested voltage between battery and cable while pulling fuses (alternator not attached)\
4)replaced battery several times

Also, when I adjust the volume on my radio (stock) by turning the knob from min to max, the volume has a dead spot. It gets louder from min to middle and then hits a dead spot, starts over, then gets louder from middle to max. Can't figure out if this is any way related to battery problem.

Please help!!!

 

Welcome to the forum . Pull the fuses for the radio and see if that helps. I think the radio has a short. Did you buy the 4 -runner used? :

 

I agree. My little bro had this car before me and I think he fooled around with the stereo, adding and removing equipment and so forth. I should make him fix it! Thanks for the reply.

 

Has the radio been wired so it will play without the key installed? Some people do this so they don't have to turn on the key to listen to tunes. Most wired like this will drain the battery.

The right way to wire is to have the "memory" wire connected to a battery fuse (hot all the time), and the switched wire connected to an accessory fuse (hot with key on or in accessory position)

 

I also have a mysterious battery drain on a '93 V6 4runner. The battery is 8 months old and if the truck is sitting for more than 36 hours the battery gets too low to start it. I have tried putting a meter in line with the -ve cable and it shows no amps flowing, but obviously there must be current draining somewhere. Anyone have any idea where the juice is going.

thanks in advance for any help

 

Use an ammeter to see how much is being drained, even if it is being drained. If there is no drain, it's just a battery that can't hold a charge, i.e. bad.

 

Don't forget to measure the battery voltage with the engine running. It should read some 13.8-14.4 Volts. If not you maybe have a good battery but a bad regulator, alternator or something like that.

 

No problem with the engine running, 14.2 volts, and the battery is charging. The voltage is 12.6 after running for a while, but drops to below 10 after a day or 2.
I tried the ammeter and there is zero current flowing, even on the 200mA scale. I was thinking of leaving the battery disconnected to check for an internal short, is that likely. Or I guess my 8 month old battery could be a dud.

 

Looks like it. Just replaced mine last week. Hadn't used it for 4-5 months during the supra swap. It was dead since than. It barely started only due to the synthetilc oil and the extrememly hot summer over here.
If it doesn't drain any current, it will leak current internaly so its time for a new one.

 

My 2 cents says your battery junk

 

found the problem this weekend, two problems actually. The fuse in my ammeter was blown so that was the reason no current was flowing. After replacing the fuse I found that almost 1/2 an amp was flowing from the battery with the key out. Turned out to be the rear power window circuit. For now the fuse on that circuit is out, finding the short will be this coming weekend's event, if this &*$# rain ever stops.

I guess the moral of this story is if your relying on readings from instruments make sure they are working and accurate.