Dual Battery

[Ditch Wicked]

A PO installed a second battery and a solenoid. It allegedly powers the front light bar, the CB, the USB charger and 3 aux back up lights. There is a deep cycle marine battery in there now, but nothing works. I suspect the batt is dead. I am wondering if it would be possible to put in a new battery and hook it into the charging system. Or would I need to add a second alt.

 

[edgephoto]

You can wire them in parallel. Hook the two positives together and the two negatives together.

You could also use a battery isolator to keep them separated nd prevent a dead battery from draining the other one.

 

[Grit dog]

There are many ways to wire in a second battery from straight up parallel connection to any number of solenoids, relays/isolators.
IMO, the bigger question is, do you really have a need for a 2nd battery? And if you do and actually use it for auxiliary loads, while the vehicle is shut off, then isolate it from the start battery, like with that solenoid there or any other means.
Unless I was planning some dedicated key-off loads, I’d spend that money on a quality start battery and the biggest alternator you could get.

 

[Ricko1966]

2nd battery,isolated is super easy and cheap,it does charge but disconnects when the vehicle is not running so you can power whatever you want until the battery goes dead. But your truck will still run on the other battery and charge the isolated battery while you dr8ve home. Bit as Grit said what do you have that you really need to run off a second battery? Maybe an illusion and I am also assuming how that isolator works without seeing any markings. But at this point It appears 2nd battery has 1 lead attached to the isolator, the light colored lead is probably the trigger wire. If that is the case all you need is to run a 16 gauge wire with a 20 amp fuse to the positive terminal of the other battery to the other large post on the isolator. Using a 16 gauge wire acts as a voltage regulator kind of,those should charge battery 2 at approximately 15 amps,still as a cheap battery charger,but not too taxing on your existing alternator,or other vehicle electrics.

 

[Ditch Wicked]

There are many ways to wire in a second battery from straight up parallel connection to any number of solenoids, relays/isolators.
IMO, the bigger question is, do you really have a need for a 2nd battery? And if you do and actually use it for auxiliary loads, while the vehicle is shut off, then isolate it from the start battery, like with that solenoid there or any other means.
Unless I was planning some dedicated key-off loads, I’d spend that money on a quality start battery and the biggest alternator you could get.

I dont know if its needed or not. I am just looking for the easiest way to get the light bar, back up lights and the CB working. I wont be using anything without the engine running. I am not great with ad hoc wiring.

 

[Ricko1966]

I dont know if its needed or not. I am just looking for the easiest way to get the light bar, back up lights and the CB working. I wont be using anything without the engine running. I am not great with ad hoc wiring.

If you aren't running these things with the Vehicle off,you do not need a second battery. You do need to wire these items correctly into your existing system. Make a list of what you need wired up,we'll help you. Or maybe we'll just argue about how it should be done. IDK make your list,we'll see what happens.

 

[Snoots]

You must be registered for see images attach

 

[Grit dog]

Bam! That’s a good wiring diagram
If you’re just wanting to roll, put your good battery over there and make sure everything is wired to it and works.
Make sure you got a charging wire to it and get er dun.
If the accessories are not hooked up right you’ll figure that out I guess. But you’ll have to figure out how it’s wired up. Not horrible because after market wiring is easy to trace. It’s the oddball **** that doesn’t look factory. Lol

 

[SquareRoot]

How many dozen lights are on that bar?

 

[Ditch Wicked]

If you aren't running these things with the Vehicle off,you do not need a second battery. You do need to wire these items correctly into your existing system. Make a list of what you need wired up,we'll help you. Or maybe we'll just argue about how it should be done. IDK make your list,we'll see what happens.

The light bar in the front, the 3 back up spot lights, the CB and the charging ports are all wired to the switches on the center console. All the switches are wired to the solenoid, and then to the second battery.I was think maybe I could just run a 12 or 16 gauge wire, with a fusible link, from the positive terminal on the main batt to the positive terminal on the solenoid. Eliminating the second batt all together. Maybe put a good batt in the second spot with a solar trickle charger so I could give myself a jump start if needed. Its 40 miles to the nearest auto parts store and 50 to the nearest walmart. Trying to get everything together to drive cross country in October.

 

[Ditch Wicked]

How many dozen lights are on that bar?

You must be registered for see images attach

Looks like 3 dozen or so LED's.

 

[Ricko1966]

That solenoid appears to be,or was used as a battery isolator. If you get me better pics,and if possible any terminal markings on it. I'd bet you I can tell you how to wire it up,or replace it with a $10.00 relay. No solar charger needed, 2nd battery would charge whenever the truck is running. Sorry won't have a diaghram for you but as simple as that is,it's going to be so easy you won't need a diaghram. I already wrote this,but it disappeared somehow. Get me better pics of that solenoid/ Isolator I'm making assumptions based on one little pic. Looks like B+ on Batt 2 is connected to the large post,the smaller lighter gauge wire I assume is the trigger wire,all you need to do is run a 16 gauge wire with a 20 amp fuse from the other isolator big post to the B+ terminal of the other battery. Using 16 gauge will act like a primitive voltage regulator,letting you charge at approximately 15 amps. No solar panel needed.To double check operation of that isolator get a 12 volt test light. Check for constant 12v on the 1st big post. 12v on little post only when the truck is running,or possibly just when the key is in the run position. Other big post should only have 12v when the truck is running,possibly just when the key is turned. If that checks out run a fused 16 gauge wire and you are done. The reason for the 2 possibilities is it depends on what the p.o. is using for a trigger,I suppose there's a 3rd possibilty,could be using a toggle switch as the trigger. Post back results you find with your test light.

 

[AuroraGirl]

That solenoid appears to be,or was used as a battery isolator. If you get me better pics,and if possible any terminal markings on it. I'd bet you I can tell you how to wire it up,or replace it with a $10.00 relay. No solar charger needed, 2nd battery would charge whenever the truck is running. Sorry won't have a diaghram for you but as simple as that is,it's going to be so easy you won't need a diaghram. I already wrote this,but it disappeared somehow. Get me better pics of that solenoid/ Isolator I'm making assumptions based on one little pic. Looks like B+ on Batt 2 is connected to the large post,the smaller lighter gauge wire I assume is the trigger wire,all you need to do is run a 16 gauge wire with a 20 amp fuse from the other isolator big post to the B+ terminal of the other battery. Using 16 gauge will act like a primitive voltage regulator,letting you charge at approximately 15 amps. No solar panel needed.To double check operation of that isolator get a 12 volt test light. Check for constant 12v on the 1st big post. 12v on little post only when the truck is running,or possibly just when the key is in the run position. Other big post should only have 12v when the truck is running,possibly just when the key is turned. If that checks out run a fused 16 gauge wire and you are done. The reason for the 2 possibilities is it depends on what the p.o. is using for a trigger,I suppose there's a 3rd possibilty,could be using a toggle switch as the trigger. Post back results you find with your test light.

id also recommend a continious duty version of the ford fender relay that replaced the ones that looked like that
And since its not original, who is to say that one in the picture is the right kind anyway

The reason Id recommend the relay version instead of solenoid is they have less potential for issues
And the simple act of over tighting the nuts on the old solenoids like that can distort them enough to shorten their life and in starter ones weld on ,but not as much in the continuous

 

[Ricko1966]

id also recommend a continious duty version of the ford fender relay that replaced the ones that looked like that
And since its not original, who is to say that one in the picture is the right kind anyway

The reason Id recommend the relay version instead of solenoid is they have less potential for issues
And the simple act of over tighting the nuts on the old solenoids like that can distort them enough to shorten their life and in starter ones weld on ,but not as much in the continuous

I don't know that that is not continuous duty,at this point we don't even know if it works. The checks I asked him to make will tell us. If it works I'd use it until it doesn't work. Then we can worry about what to replace it with. At this point we need to see if it works.