Thread: Newby with new LR4 doesnt want to alter wiring.

Apologies all if you have seen this post in another thread, just that the thread seems to have run its course and I do need some help. I have a 5 day old LR4 which I have no desire to modify and risk voiding my manufacturers warranty. I would like to use the 12S socket (White european socket) to power the Redarc Battery Chrger about to be fitted in my Camper Trailer as opposed to replacing it with a heavy Anderson plug. The forums have scared the living daylights out of me becasue for some reason no one trusts this plug and this is in conflict with my UK towing experiences so I am asking for some help below to assist my understanding of the problem. I am also offering some thoughts which might explain why some are experiencing overload problems. Please, I am new to the forums and won't assume that everyone has the same competentency/knowledge of electrics so forgive If I am teaching granny to suck eggs here. Thats not my MO


Statements made in the following text are up for critique guys, I am no expert in this and am looking for someone to convince me that my thinking is incorrect. PLease do help as I am unsure which way to proceed. I have also contacted Land Rover and will gladly feed back the response when I have it.

I spent some time trying to identify the fuses (from my manual) which are in line with the various pins of the white 12S socket on the rear of my 2013 LR4.

My attached drawing is produced as you would view the socket with the socket orientated the correct way as to my car. (location tab at 3 o'clock position. I established the battery 12V (full time live) position and followed the conventional 12s Wiring plug drawings to identify others from this benchmark. But I cant agree with the drawings that I have seen in that the blue pin at the 10 ish position appears to be disconnected as no change to the vehicles ignition etc would power this pin and it isnt an earth either.. If anyone can help me here please do.

There is an advantage wiring loads to the igntion circuit in that the alternator will be used to power the load as opposed to the cars battery thereby protecting the cranking battery from discharge. The problem wiring heavy electrical items directly to the ignition pin though is that it is only fused at 15A and at 12V this will only power a very small battery charger or a small recreational fridge but possibly not both. Better by far, from what I see which needs some confirmation or otherwise, is to have suitable isolation from the cranking battery and wire heavy items from the battery positive pin so is a possible solution then to swap this 30A feed over to your aux battery if running a dual system? After all this is what people do with 12v sockets which feed on board fridges etc and 30A should power just about any mobile fridge I know of.

As I said, I won't be doing this until the warranty is up but I plan to use the ignition feed (12v+ with ignition) as the connection to a Redarc 12v 25A dc dc charger as the indication that the ignition is on (alternator running) but the charging current will be delivered via this battery feed pin (30A) Has anyone else fitted anything like this system and got away without stripping out the 12S socket.


All help or comments more than welcome.

Originally Posted by drivesafe

Hi Muddy and you need to do a lot more research before doing anything to your D4.

For a starter, you do not need to rip up any carpet to run decent sized cabling through your D4, you simply run the new cabling with the vehicle’s existing wire looms and I mean you SIMPLY run the cable because the D3 and D4 are the easiest vehicles I have ever come across for running cabling through.

Next, you shouldn’t need a DC/DC device in your CT as the D4 will easily charge a bank of batteries and still have heaps of power left over for everything else in the D4.

There are plenty of D4 owners on here who have a cabling set up ( ne DC/DC Device ) and have no trouble maintaining their CT or caravan batteries.

As above, do some more research because you can set up a better system for a lot less money than a DC/DC device will cost you.

Thanks Drivesafe. I'm not sure that I'm with you on wiring heavy cable through the existing loom. Do you mean that there is a conduit along which to push these cables or is the loom external to the vehicle and the cables simply clip in? Would love to learn more if possible as if this is the case I might do this myself. Would go and look underneath but it's raining .

I have already bought the BCDC1225 charger (ebay $320) as this unit accepts a solar panel input also so it will work for me on the move as well as at camp. I also bought it thinking that my AGM on the CT needs more careful charging than a simpler lead acid until today when I dscovered my cranking battery is AGM also so the LR output should be kind enough Oh Well! My camper deep cycle battery is well maintained prior to leaving home and I should never need to go below 60% charge with just a fridge and a few lights.(I have a calculated current draw from a 100A/Hr battery of 40A over 24 Hours (worse case scenario). With a 5A output from a 120W solar panel again (pessimistic numbers) I should get sufficient sunlight to restore the battery and if not due to bad weather, a top up from the car will do it.

If you feel like shedding any more light about running thos cables I would love to hear more.