???dual battery????

[Twood2006]

So I went out side earlier to go somewhere and my battery was dead so I lifted the hood up and looking at the motor from front the battery on the right side behind the drivers headlight I unhooked it to see if that turned my interior lights off or anything but it did not do anything everything still worked just don’t have enough power to start vehicle so I hooked it back up and then unhooked the batter on passenger side and that killed all power to vehicle so my question is the other batter when I unhook it nothing changes it does not lose any power or anything so is it possible I could just take the battery on drivers side and replace it with other battery so that I can start vehicle I was hoping that both battery’s were hooked up so I would not really have to deal with the dead battery situation

 

[LordWayback]

1st off make/model year , trim , what engine unless you have a duramax there’s no factory dual battery system as even a option
2nd of all I would start at the junction box unless you know that both batteries are balance charged and the junction is good unless this is some jank setup there’ll be a junction on which the battery has a breaker or a fuse.
3rd give us specifications on the batteries, date sticker etc
4th if you can’t start the truck on one battery unless the battery is super dead/old you have other issues. It shouldn’t be cold enough right now to cause cold start conditions unless you’re trying to start it up at like 5 am or something
5th Pictures Please!

 

[OR VietVet]

C,mon man! Basics first. Like @LordWayback asked for.

 

[swathdiver]

So I went out side earlier to go somewhere and my battery was dead so I lifted the hood up and looking at the motor from front the battery on the right side behind the drivers headlight I unhooked it to see if that turned my interior lights off or anything but it did not do anything everything still worked just don’t have enough power to start vehicle so I hooked it back up and then unhooked the batter on passenger side and that killed all power to vehicle so my question is the other batter when I unhook it nothing changes it does not lose any power or anything so is it possible I could just take the battery on drivers side and replace it with other battery so that I can start vehicle I was hoping that both battery’s were hooked up so I would not really have to deal with the dead battery situation

The batteries are isolated for powering different things but are charged together on a TP2 system. To get the truck started, physically swap them. They ought to be replaced in pairs for max life.

 

[Twood2006]

1st off make/model year , trim , what engine unless you have a duramax there’s no factory dual battery system as even a option
2nd of all I would start at the junction box unless you know that both batteries are balance charged and the junction is good unless this is some jank setup there’ll be a junction on which the battery has a breaker or a fuse.
3rd give us specifications on the batteries, date sticker etc
4th if you can’t start the truck on one battery unless the battery is super dead/old you have other issues. It shouldn’t be cold enough right now to cause cold start conditions unless you’re trying to start it up at like 5 am or something
5th Pictures Please!

It is a 2015 ppv tahoe 2wd it has dual battery’s

 

[Twood2006]

 

[Twood2006]

I ended up replacing the battery on the left side of the engine looking at it when I had it tested it said it was a bad battery but now that I replaced it I have not had anymore problems with it I was just thinking with 2 battery’s they would be ran together but when the battery was to weak to start it all it would do was run all the lights and radio and everything but would not start the vehicle I ended up unhooking the battery on the right side of the engine and none of my lights went off or radio or anything so I do not think it is hooked to anything unless it goes to the plug on the inside of my vehicle like a wall plug in your house I guess that is where they used to plug their computers up at it still works as long as the vehicle is on as soon as it goes off the plug stops working I just want to figure out a way to run battery’s together so if one goes dead the other could still help power things to start the vehicle

 

[Doubeleive]

I ended up replacing the battery on the left side of the engine looking at it when I had it tested it said it was a bad battery but now that I replaced it I have not had anymore problems with it I was just thinking with 2 battery’s they would be ran together but when the battery was to weak to start it all it would do was run all the lights and radio and everything but would not start the vehicle I ended up unhooking the battery on the right side of the engine and none of my lights went off or radio or anything so I do not think it is hooked to anything unless it goes to the plug on the inside of my vehicle like a wall plug in your house I guess that is where they used to plug their computers up at it still works as long as the vehicle is on as soon as it goes off the plug stops working I just want to figure out a way to run battery’s together so if one goes dead the other could still help power things to start the vehicle

not sure how yours is hooked up currently, but you can run them parallel. All you would need to do is run a power wire from the 2nd battery positive to the starter.
before you do that check how it is wired currently it may be running the 2nd battery to accessories only if so there will be a isolator.
you wouldn't need to make any other changes to run them parallel because it will charge the 2nd battery from the starter post where the 1st battery is already connected.

 

[Twood2006]

not sure how yours is hooked up currently, but you can run them parallel. All you would need to do is run a power wire from the 2nd battery positive to the starter.
before you do that check how it is wired currently it may be running the 2nd battery to accessories only if so there will be a isolator.
you wouldn't need to make any other changes to run them parallel because it will charge the 2nd battery from the starter post where the 1st battery is already connected.

Thank you I am going to check how it is hooked up tomorrow when I get home

 

[Doubeleive]

Thank you I am going to check how it is hooked up tomorrow when I get home

are your battery's both the same size/type i.e. H6 or H7 or are they one of each? just curious another member was asking about this because of the 2nd battery tray size