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I wanted to share with you all a small mod I did today that add something to the Disco that is much needed, an “always-on” 12v outlet in the load space area.
As you are probably aware, the 12v outlet in the rear of the vehicle is, normally, only on when the power is on. Which means after you cut the engine you have about 3 minutes before it cuts out. Rendering it pretty much useless while camping, or for running something like a fridge.
But I have resolved that problem, using just a small piece of wire and quick disconnect.
So while researching this problem I came across a wiring diagram that noted there is a vestigial wiring harness under the load deck, behind the styrofoam spare tire surround. This wiring harness is intended for some sort of European trailer hitch or something. But importantly, it contains a “hot” 12v pin wired to a 15A fuse.
You can access the harness by removing the load deck, the left side foam piece closest to the tail gate, and the plastic kick plate on the tailgate, which is just held in by clips and pulls right out with a good tug, with no risk of breaking pins. Against the tailgate you’ll see 2 large harnesses, 1 grey and 1 green. The green one is connected, but the grey one is just sitting there empty. The grey connector is this vestigial trailer hitch connector.
![7531]()
Now, what’s great, is that the GREEN one, right there? That goes to the loadspace 12v outlet!! How convenient.
Onthe green connector the black wire with green strip goes to ground (you can see where it’s grounded in the lower right corner of the photo above, along with a bunch of other black/green wires.) And the brown wire with yellow strip is a aux power line, that is hot only when the car is on, no good.
Now, looking in the grey connector, you’ll see a purple wire coming in the back, it is the 2nd pin from the left on the “short” row of connectors.
![7532]()
Testing this with a multi-meter you’ll be able to confirm that it is indeed “hot” and reads ~12v when the car is fully turned off. This is our target.
You can connect to this pin using a 7/64” Female Disconnect. Through trial and error I figured out this size, it is PERFECT. Holds securely. I recommend a fully insulated version of this connector, just to be 100% certain it can’t move and cause a short, but the risk of that is minimal. It is just as secure as a factory plug, I had to use a pliers to pull the test one off.
So, all you need to do is put one of these connectors at the end of a short 16 gauge wire, I made mine about 12” long, but this was VERY excessive. I might redo it with just a 6” wire.
At the other end of the wire, use some sort of disconnect. I used “bullet” style disconnect, because for whatever reason I really like them, I usually use them.
So connect the female end to the other side of your make-shift jumper, that way if it does come loose you don’t have a naked 12v hot wire rattling around.
Then just sip the brown/yellow wire going into the green harness from the right. I snipped it about half way down, and attached a male connector to the side coming off the harness.
For safety sake connect the jumper to the green harness wire FIRST, then to the pin in the grey harness.
TAKE PRECAUTIONS, THE PIN IS CARRYING A HOT 12V CHARGE.
Final product should look like this.
![7533]()
,
![7534]()
and voila, that’s it. You now have an always-on 12v outlet in the loadspace.
As you are probably aware, the 12v outlet in the rear of the vehicle is, normally, only on when the power is on. Which means after you cut the engine you have about 3 minutes before it cuts out. Rendering it pretty much useless while camping, or for running something like a fridge.
But I have resolved that problem, using just a small piece of wire and quick disconnect.
So while researching this problem I came across a wiring diagram that noted there is a vestigial wiring harness under the load deck, behind the styrofoam spare tire surround. This wiring harness is intended for some sort of European trailer hitch or something. But importantly, it contains a “hot” 12v pin wired to a 15A fuse.
You can access the harness by removing the load deck, the left side foam piece closest to the tail gate, and the plastic kick plate on the tailgate, which is just held in by clips and pulls right out with a good tug, with no risk of breaking pins. Against the tailgate you’ll see 2 large harnesses, 1 grey and 1 green. The green one is connected, but the grey one is just sitting there empty. The grey connector is this vestigial trailer hitch connector.
Now, what’s great, is that the GREEN one, right there? That goes to the loadspace 12v outlet!! How convenient.
Onthe green connector the black wire with green strip goes to ground (you can see where it’s grounded in the lower right corner of the photo above, along with a bunch of other black/green wires.) And the brown wire with yellow strip is a aux power line, that is hot only when the car is on, no good.
Now, looking in the grey connector, you’ll see a purple wire coming in the back, it is the 2nd pin from the left on the “short” row of connectors.
Testing this with a multi-meter you’ll be able to confirm that it is indeed “hot” and reads ~12v when the car is fully turned off. This is our target.
You can connect to this pin using a 7/64” Female Disconnect. Through trial and error I figured out this size, it is PERFECT. Holds securely. I recommend a fully insulated version of this connector, just to be 100% certain it can’t move and cause a short, but the risk of that is minimal. It is just as secure as a factory plug, I had to use a pliers to pull the test one off.
So, all you need to do is put one of these connectors at the end of a short 16 gauge wire, I made mine about 12” long, but this was VERY excessive. I might redo it with just a 6” wire.
At the other end of the wire, use some sort of disconnect. I used “bullet” style disconnect, because for whatever reason I really like them, I usually use them.
So connect the female end to the other side of your make-shift jumper, that way if it does come loose you don’t have a naked 12v hot wire rattling around.
Then just sip the brown/yellow wire going into the green harness from the right. I snipped it about half way down, and attached a male connector to the side coming off the harness.
For safety sake connect the jumper to the green harness wire FIRST, then to the pin in the grey harness.
TAKE PRECAUTIONS, THE PIN IS CARRYING A HOT 12V CHARGE.
Final product should look like this.
,
and voila, that’s it. You now have an always-on 12v outlet in the loadspace.
I loved Colorado when I visited! Feel free to share your setup with fridge/inverter too - I'd be interested to see how you configure things for overlanding.
