For my dual battery setup I used Slee's battery tray and Blue Sea System's ACR & switch.
Both the Blue Sea System parts come as a kit, West Marine carries them.
The ACR (battery isolator) also has two extra connections, one to drive an LED to indicate it has connected batteries, and an override to disconnect it. Not sure override is needed as it does not come on until charge voltage is achieved and has a delay built in. The switch has three positions, Off, On and Combine, diagram shows it in On position.
WestMarine - Blue Seas Add a Battery Kit 120 Amp
[link updated 8/14/2020 - price $120]
From the wiring diagram below you can see I did the wiring a little different. I have been running it for almost two years and have been happy with it.
Battery 1 goes to Big Red Switch and ACR, on other side of switch is winch and only primary to starter.
Battery 2 goes to other side of Big Red Switch and ACR, also tied to this terminal is fusible link box that has everything else in vehicle, including alternator.
If you have drained battery 2 (long nights, lights, power invertors, etc), then just flip Big Red Switch to combine and fires right up. You could hook fusible link box to switched side of Big Red Switch for Battery 2, but I did this way so alarm and keyless entry work when Big Red Switch is off, also the ECU does not get reset..
Made a bracket to mount ACR with Big Red Sw on its top that fits near stock battery location. Next post will have Battery 2 and compressor mounting.
What do I see as pluses for this setup.
1. Starter motor current surges are isolated from everything else (at least greatly reduced, when you use combine for jumping or with winch will see them then)
2. It does not matter what device is left on (lights, radio, fridge, etc), it only drains Battery 2
3. Can kill power to winch and starter, to keep folks from playing with winch.
4. Alarm and keyless entry work and the ECU does not get reset when Big Red Switch is off.
By changing placement of the fusible link box and wiring on the switch many combinations of switching and load assignments to batteries can be utilized.
While this sounds tricky to do, the stock wiring makes it somewhat easy. At the battery there is the large wire that goes to the starter and a fusible link box, both bolt to battery terminal. The fusible link box feeds everything else including power to ignition key and engine computer, also has alternator feed.
I rewired the fusible link box so it bolts to bottom of switch with Battery 2, some tape to protect from dropping a tool on it. See photo below.
Wiring diagram (where wires cross without a dot = no connection)
Both the Blue Sea System parts come as a kit, West Marine carries them.
The ACR (battery isolator) also has two extra connections, one to drive an LED to indicate it has connected batteries, and an override to disconnect it. Not sure override is needed as it does not come on until charge voltage is achieved and has a delay built in. The switch has three positions, Off, On and Combine, diagram shows it in On position.
WestMarine - Blue Seas Add a Battery Kit 120 Amp
[link updated 8/14/2020 - price $120]
From the wiring diagram below you can see I did the wiring a little different. I have been running it for almost two years and have been happy with it.
Battery 1 goes to Big Red Switch and ACR, on other side of switch is winch and only primary to starter.
Battery 2 goes to other side of Big Red Switch and ACR, also tied to this terminal is fusible link box that has everything else in vehicle, including alternator.
If you have drained battery 2 (long nights, lights, power invertors, etc), then just flip Big Red Switch to combine and fires right up. You could hook fusible link box to switched side of Big Red Switch for Battery 2, but I did this way so alarm and keyless entry work when Big Red Switch is off, also the ECU does not get reset..
Made a bracket to mount ACR with Big Red Sw on its top that fits near stock battery location. Next post will have Battery 2 and compressor mounting.
What do I see as pluses for this setup.
1. Starter motor current surges are isolated from everything else (at least greatly reduced, when you use combine for jumping or with winch will see them then)
2. It does not matter what device is left on (lights, radio, fridge, etc), it only drains Battery 2
3. Can kill power to winch and starter, to keep folks from playing with winch.
4. Alarm and keyless entry work and the ECU does not get reset when Big Red Switch is off.
By changing placement of the fusible link box and wiring on the switch many combinations of switching and load assignments to batteries can be utilized.
While this sounds tricky to do, the stock wiring makes it somewhat easy. At the battery there is the large wire that goes to the starter and a fusible link box, both bolt to battery terminal. The fusible link box feeds everything else including power to ignition key and engine computer, also has alternator feed.
I rewired the fusible link box so it bolts to bottom of switch with Battery 2, some tape to protect from dropping a tool on it. See photo below.
Wiring diagram (where wires cross without a dot = no connection)
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