84 720 battery drain

[Berkybot]

The battery has been draining while my truck is off. It wasn’t an issue until the truck sat a couple days while I was out of town, so I am assuming it’s a fairly slow drain. I just replaced the alternator a week ago. Any idea what it may be? Thanks for the help.

[Thomas Perkins]

First,drive to Auto part store and check battery and Alternator.Check your black wire to white wire on your fusible link. It goes to alternator. Are your black and white wire on  the back of alternator clean.Check the ground coming from end of negative battery terminal to ground post at power steering bracket.Get a scrub pad and clean them all.Make sure alternator belt is tighten and not moving.Mark it with a  Marker so you will.know if the belt is getting loose,not holding tension.

 

[Berkybot]

52 minutes ago, Thomas Perkins said:

First,drive to Auto part store and check battery and Alternator.Check your black wire to white wire on your fusible link. It goes to alternator. Are your black and white wire on  the back of alternator clean.Check the ground coming from end of negative battery terminal to ground post at power steering bracket.Get a scrub pad and clean them all.Make sure alternator belt is tighten and not moving.Mark it with a  Marker so you will.know if the belt is getting loose,not holding tension.

 

I had my local mechanic check the belt after I replaced alternator so that shouldn’t be the issue, so I hooked up a charge tester to one of the battery wires and pulled fuzes until the circuit was closed. It ended being the taillights fuse. Thing is I don’t believe they were working anyways, my truck has a custom flatbed so I’m assuming there is a wiring problem there and will just rewire the taillights. I’ll check the volts on the battery and try to start the truck tomorrow and see if it is still draining. If not I will just rewire the lights.

[datzenmike]

Pull one of the battery cables off and connect a test lamp between them. If there is a draw it will light.

 

Remove fuses till the lamp goes out. The last fuse removed has something on the circuit that is active. It won't be anything turned on by the ignition or the light switch as they are switched off. It will be fuse 8 through 13 that are powered at all times such as the interior lamp, brake lights, horn, clock.

 

 

[Thomas Perkins]

6 hours ago, Berkybot said:

I had my local mechanic check the belt after I replaced alternator so that shouldn’t be the issue, so I hooked up a charge tester to one of the battery wires and pulled fuzes until the circuit was closed. It ended being the taillights fuse. Thing is I don’t believe they were working anyways, my truck has a custom flatbed so I’m assuming there is a wiring problem there and will just rewire the taillights. I’ll check the volts on the battery and try to start the truck tomorrow and see if it is still draining. If not I will just rewire the lights.

Great.I hope it works out for you.