Hello all, suffering from a servere battery drain issue and I've managed to get it to my mechanic and we're slowly trying to find the source of the draw.

Pulling various fuses isn't conclusive but wondering what these wires situated behind the battery are connected to?

The drain is predominantly coming off of the lower 50amp wire (4th one down). There's also a draw from the second one down 40 amp.

A little more info on this one. The 5.0 supercharged I picked up in January I had trailered back to the dealer last month whilst it was still under warranty as the EML kept coming up indicating cam position actuator issue by the iid tool. This was allegedly rectified by sorting out some wiring to the ECU so I spent the day on public transport to collect the car.

Halfway into the journey home the engine light came on again but I didn't have my IID tool with me. It was a bit lumpy at low revs as before but I needed to get home so persevered and stuck half a tank of super in and seemed to level out after some constant motorway miles.

Next morning at 6am expecting to drive the 5.0 to work the car won't start and the dash flickers off and doesn't even manage to the first stage of ignition. Start button does nothing but the blowers, radio and deployment are still active.

Later that day I swap out the battery for a known good one and it starts up first time although every error flashes up on the dash. I take it for a drive around the block and perform a vehicle reset via the iid tool and it seemed ok so I thought I'd wipe down the car ready to use in the evening. 30 minutes later the car won't start, dash flickers off and I'm left once again with an oversized paperweight.

I pulled and charged up the battery so that it would start, I dared not switch it off and tool it directly to my mechanic at work. It lit up all the errors and warning lights and steering went heavy at times and the fan was working overtime for the entire half hour journey.

Since then it hasn't moved and it's seeing a 12 amp draw when the 4th wire down (behind the battery) remains connected.

Electrics are not my mechanic's strong suit so I'm really hoping someone can shed a bit of light or point us in the right direction.

Thanks in advance!

What about arranging for a mobile auto electrician to take a look whilst the vehicle is at your mechanics place. Might save you a lot of time and money in the long run 2011 TDV8 Vogue SE

As a start, With the 4th wire down disconnected,
what doesn't work? 2018 SE SDV8 4.4 Byron Blue

Is it the 4th wire down with a 50A fuse? shown disconnected?

Presume it's the Engine JB (sorry my system is L405 so not familiar )P108 ? If so this may be the wiring diagram

In the Wiki there is a electrical library this may be the legend guess it depends on year etc


 2018 SE SDV8 4.4 Byron Blue

I think an auto electrician is on the cards if he's still scratching his head tomorrow!

Thanks for the input Kot, I've sentence him the diagram as a reference. The 4th wire down is 50 amp. We need to compile a list of ancillaries which aren't operational when disconnected.

So... Does anyone have a contact of a decent auto electrician in the SE London area? I've tried getting in touch with all the locally listed ones but none of them will even answer their phones. I wonder if my number is listed as a Range Rover owner and they've got their barge poles out?

Bit of an update on this issue. It's still laid up and hasn't turned a wheel since the original post but last week an auto spark paid it a visit and diagnosed it as being a faulty instrument cluster which is causing the parasitic drain.

The remedy is to remove the the digital unit and send it off for repair. Cost is tbc and it's still in dash at the moment.

I'm wondering if these units are plug and play? If so I was considering sourcing a secondhand unit and just swapping it over.

There’’s a chap in Leamington Spa who does dash / instrument binnacle rebuilds for D3’s and is a wizard with such things - he did our daughters while she waited and offers a fully guaranteed service.

Let me see if I can find his contact details and I’ll message you..

Sorry, Rugby, not Leamington...

Here you go - they don’t detail RR instruments but do say to call as they can do any instrument cluster!

https://totaltronics.com/cat/land-rover/

Hope this helps.

Let me have the numbers from yours, i have a couple kicking around here sir...

I assume you have unplugged the usual suspects like the FSR ?

Thanks guys this is all helpful stuff!

Craig, to which numbers are you referring?

Part numbers or engineering numbers on the label or printed in the plastic on the screen sir... 👍