Hi Folks,

I picked up this 04 Disco, did some cleanup, now on to the actual offroad build. This post is about the aux power distribution system. I have a plan, please put holes in it for me

After some debate, I've decided to put the aux relay box in the boot, in one of the storage bin areas behind the wheel well. The previous owner fubared an aftermarket amplifier there, so its got holes and cutouts already, so i decided id put it there. I'll be putting:
ditch lights (golden rover mounts, which are great, shipped fast and fit perfectly)
roof light bar (not sure yet, happy to hear suggestions)
rear work lights (found some rain rail mounts from some youtube vid that looked great, snagged a couple of those for cheap)
rock lights (maybe, the set i got is cheap as h.e. double hockey sticks.. not sure if i want to bother with these, plus the wires are short.. sigh)
TrueMods 6 port switch and relay box w/4 pin relays

The parts that need review, the plan calls for:
1. 6g wire from engine bay to aux panel busbar to supply 30 pin for all 6 (4 in use, 2 for addons later).
2. aux panel busbar all pin 85's and then 10g to ground somewhere in the back near the panel
3. two conductor 12g from aux panel from pin 86 and 87 to the front dash and lights (86 to switch, 87 to light)
4. engine bay 12v busbar (second battery) to input pin on 5 post switches
5. engine bay acc 12v bus bar for LED 12v power pin on the 5 post switches (so the LEDs switch lights when key is on, but is off when not. The idea here is i want to turn the lights on without the car on, via the second battery, but not have the switch LEDs glowing day and night)
6. engine bay ground busbar to ground each light (so I don't have to run additional ground wires from the back to the front)

big thank you to anyone that takes the time to have a look into this, appreciate the feedback good or bad. Please don't hesitate to rip it apart if I've proposed to do something stupid!
thanks,
-james

 

Very interested in this - please keep posting your progress.
- Where are you putting the second battery? My engine compartment is "stock", no room unless I start moving/deleting items. I've thought of putting it in the "boot" where one of the back seats (SE7) is or behind the passenger seat, but it would require some decent size cables (I'd like to have the winch connected and some other accessories connected to this battery). I'll use a Blue Sea Automatic Charging relay. What "aux power distribution system" are you looking at? The other important item would be to ensure the battery box is SECURE - last thing I want is for a battery to be flying around, in the vehicle, in case of an accident or roll-over. I'll more than likely go with a wet cell, size 31 battery (marine).

It would be great to see pictures of dual battery installs/setups in a Disco!

Thanks,
Gregg

 

I struggled with this too, but found an Italian website (mdi4x4.it) that has an engine bay dual battery tray, it was expensive though once you add shipping. Worth it to me for the simple fact that i already spent hours scouring the internet without success and really dont have the skills to build it myself.

As for the power distro, i got a True Mods relay box off amazon, inexpensive. I'm mounting it in the spot where one of your rear seats would fold into since mine is an SE, i have plastic bins there that cover the mass of wires.

 

Can you verify the URL: mdi4x4.com Thanks!

 

https://www.mdi4x4.it/en/prodotto/dual-battery-holder/

sorry, its '.it'

 

you can modify the stock box to fit 2 batteries. It's tight and you lose the bottle jack area somewhat but it's very doable.

On these to me light bars don't really fit the vibe. Round lights are the way to go imo and you very much get what you pay for. Rock lights I have a cheap kit and it kind of wreaks havoc on my car lol so I unhooked it. Of all the lights I have good legal fog lights and rock lights probably the most useful. These aren't fast enough to justify imo a ton of high power forward facing light, also if night wheeling a spotter is required then they are essentially useless as you just blind your spotter... Rock lights (esp ones with variable color as yellow/amber does not attract bugs like white light does) are amazing if night wheeling and great around the campsite. I've found I use ditch lights the least, somewhat nice for looking for a campsite without having to pull all the way into the pull off but other than that kind of useless to me. Small yellow baja S2 work lights on the sides of the rack again great for night wheeling and camping. Baja squadron sport rear facing dust light is just that and nice for camp as well (driving combo pattern)

 

The project

True mods relay box on some scrap plexiglass

Wired up


Where it will mount

Yeah, not quite done pulling wires

 

I recommend that you think hard about powering your winch off a battery mounted aft. You want your winch cables as short as is practical. You might have compelling reasons to want that, but "Just Cuz" is not a very solid reason.

 

especially when it fits in the front right in the stock location with minimal modifications.

 

Had some time today, got the work/back lights wired to the relay box area through the little hole in the roof rain rail seam and the light mounts installed. Still have to wire up the 12v to 5v usb-c adapter for this other dvd delete project im working on, then i can put the headliner back in. Long story, but there was a leak I thought was the sunroof, turned out to be the roof rail leaking (which is why i removed them)... then i got an idea... and, well, now i have another mess. I can post all that if you guys are curious, essentially im 3d printing a ipad mount/holder to fit in the dvd units place drop in to the original outer dvd trim, but had to stepdown to 5v and usb-c to get it to work.