2015/16 LR4 Dual Battery Setup?

NYCRover

Observer
Hi- I know there have been some threads about this and it seems like there is simply no space in the engine bay to fit a dual battery given the 2nd eco start stop battery and dual air filters. So I bought a National Luna Portable Power Pack out of a lack of other options and was thinking about mounting this on my front runner drawer system to power lights and a fridge while camped and connecting it to the main battery. The problem is, the grommet through the firewall is so small that I don't think i can run the wires from the portable power pack through the firewall to the main battery without drilling a hole (i don't want to do this). So I guess my other option is to route it underneath the car following the brake lines and up through the tail light opening where the trailer wiring goes.

Has anyone done this? Was also wondering if anyone has seen a 2015+ LR4 dual battery setup or figured out a way around this.

This is the last step for my LR4 build, so it is kind of frustrating Im hitting a road block. Any input would be much appreciated.
 

nwoods

Expedition Leader
The LR3’s had a large, difficult to reach spare firewall grommet directly below the main wiring loom. Alternatively a number of people found it easier to simply poke through the steering column grommet. Be sure to seal them up because they are both a bit low.
 
My Traxide harness is going through the steering column grommet as it is the best and easily accessible (easy is relative to other options); however, as @nwoods stated, the main harness comes through the firewall at the passenger side interior fuse panel under the dash. Taking the glove box cubbies out is relatively easy to get the main harness disconnects and there is plenty of room to fish the harness there. Ideally, I will move my harness to there with a bulkhead disconnect such as an Anderson Plug or firewall passthrough (requires drilling but waterproof and used in most racing applications/Summit Racing cheap).

To remove the fuse box, two 10mm(?) nuts on the bottom of the fuse box and then it falls right out. The main disconnects are on the level-lock connectors so pull the lever back and the connector will come out of the bulkhead connector.
 

LR4XFAR

SCLR member 2013 LR4 HD
There's a nice sized grommet on the firewall outboard and a couple of inches above the brake pedal steering shaft. If you pull the semi flexible grey cover down, you'll see it. I cut the corner off and pulled the grommet into the cabin. I may have had to push it towards the front of the car into the engine bay. You'll probably need to remove the other battery temporarily to recover the grommet. From there poke a hole in the grommet, feed the cable through it (I would reverse the grommet to that it inserts from inside and push the cable from inside the cabin through the hole. The cable will be under the brake master cylinder. Needle nose pliers will grab it easily. Much easier to go from inside to outside!
 

AdventureTim

New member
Great timing, I’m going through a very similar thing on my 2015. I decided to get a Renogy 100Ah LiFePO4 battery so I can mount it in the cabin behind the back seats. I’m using a REDARC DC-DC/solar charger to charge it and need to find a solid 40A input. I’ve previously tee-d into the thick gauge wiring that goes to the stop/start solenoid for driving lights and I plan to do the same for the battery charger, but haven’t found a way through the firewall just yet.
 

NYCRover

Observer
I've pretty much given up on a dual battery system for the LR4 as I won't really be able to utilize it as I really want (run winch, aux lighting, etc.) given the likely location of the second battery in the cabin.

I ended up buying a dometic portable battery (https://shop.dometic.com/store/dome...MIndGz15iz5AIVbx-tBh0EWgEbEAQYASABEgKYj_D_BwE), which worked great on my 2 week trip peddling around Montana and Idaho. Worked well in different ambient temperatures and could probably go 2 full days running my fridge and camp lighting without a charge. The battery charges while your driving around plugged into a 12v socket in the car. It has a smaller footprint than the NL portable power pack and I don't have to run any wiring in/out of the car. It mounts nicely on my Frontrunner drawer system, strapped down with a small stratchit. Not exactly what I wanted, but a convenient (albeit expensive) option for those in a similar situation/needs.
 

John R

Active member
I've pretty much given up on a dual battery system for the LR4 as I won't really be able to utilize it as I really want (run winch, aux lighting, etc.) given the likely location of the second battery in the cabin.

Not following, doesn’t it fit between the passenger headlight and the main battery? I’m assuming I have a 3.0lt
 

perkj

Explorer
I've pretty much given up on a dual battery system for the LR4 as I won't really be able to utilize it as I really want (run winch, aux lighting, etc.) given the likely location of the second battery in the cabin.

@NYCRover you NEVER want to run your winch off a secondary battery. You always want it wired to the primary as it is the battery connected straight to the alternator.
 

TOUGE

Active member
Not following, doesn’t it fit between the passenger headlight and the main battery? I’m assuming I have a 3.0lt

I thought the V6SC has air intakes on both sides? So there is no room there for the battery outside of the battery boxes. Diesels only have 1 air intake giving you extra room in the engine bay.

I just did a dual battery on my 2012 LR4. I put it where the battery would go if I had a RHD vehicle, a 34 size JUST fits. You have to move the transfer case control module by making little brackets to bolt it to the alram horn bracket, didn't take too long. I also just ordered a new battery tiedown and bolts from Land Rover, that took a few days to get in. I made my own cable and used a Blue sea ML-ACR as the change over relay.
 

NYCRover

Observer
the SCV6 has dual air intakes as well as a second little barbie jeep battery that runs the car for the eco/start stop.
 

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