I've been dealing with an intermittent battery drain issue on my 2010 LR2 ever since I've owned it. It can go a full week without issues, or the truck can drain the battery (from fully charged to completely flat) within a couple of hours.
I've been dealing with this for 10 years, addressing the following potential culprits: new battery x 3, alternator, trunk latch solenoid, wiring to the cooling fan showing corrosion, Bluetooth antenna. Each of these fixed the problem for a few weeks, but the battery drain kept coming back.
After major arguments with Land Rover Canada, I was about to sell the truck. But then I decided to change the rules of the game, and hit the annoying mosquito with a hammer.
I installed a remote controlled battery cut-off switch, in such a way that I'd kill the battery after locking the truck. It's an extreme measure, but that was my last resort.
Here's how I went about it....
Remote kill switch

This switch fits in series with the ground cable, which conveniently bolts to the car chassis right behind the battery.
Step 1: Remove only the front clip holding the plastic cowl trim, so you can lift the cowl and gain access to the ground bolt.





The next step was for me to flip the battery 180 degrees to facilitate the wiring process. The Positive lead is now where the negative was, and vice versa.

Here's roughly where I decided to fit the relay.


I got a 1-Gauge ground wire that would go from the relay, to the OEM bolt that holds down the ground to the chassis.


Then I trimmed the plastic where the positive cable exits the battery box to route the new cable.


And bolted down the new negative cable where the OEM negative was.



The battery kill-switch didn't seem to be fused, so I wired this in-line fuse to the positive lead.


Here's what the kill-switch looks like when it's ready to be installed. Notice I also soldered some proper loop terminals on the positive and ground wires going to the battery.


I used this stock bracket to mount the relay, added a 90-degree metal bracket and a metal rail to mount everything. Use your creativity here, there's no right or wrong way to do it.


Everything in place, and I put the 2 small lead wires in a plastic loom and passed them right under the new blue negative cable.


One final trim in the plastic battery cover to accommodate the new cable, and everything was ready to be reassembled.


Final verdict: This is how I decided to stop fiddling with these multiple and random power draws. So far, I've seen no disadvantages from applying this solution. The alarm will obviously be deactivated when you kill the switch, but 1) it was going off randomly anyways, so that's an added benefit, and 2) nobody will be able to steal your truck with the battery cut-off.
So now I hit the "unlock" button on the kill-switch to activate the battery, unlock the truck using the factory remote, and I'm on my way. When I park the truck, I lock it using the factory remote, then hit "lock" on the kill-switch which deactivates the battery.
So far, I've had no issues other than the obvious: the clock is always faulty! lol

 

Smart - looks like I may be having the same problem. Good to know it can be worked around if it comes down to it. Thanks for sharing your knowledge on the subject.

 

There's a very good reason virtually no one uses hammers to deal with mosquito problems...

Well, of course, if you disconnect the battery it won't discharge, but you lose the computer sync and info, you lose the time in the radio, and you have to wait a few minutes after reconnecting it before you start the car or you may have issues with the engine not running right until the computer syncs again. All the accumulated data in the computer is also lost, and if you take it for the yearly inspection like that they will provisionally fail you until you wait a few weeks for all tests to be completed over time. You also lose the alarm's feature of triggering if an unknown key is inserted into the slot. The car can still be stolen, just not with the engine running. With the battery off, the tilt sensor will be disabled and no alarm will sound if the car is towed. If you have any children or take pets with you in the car, the worst part of it is that the interior space sensor that detects air movement in the car when the alarm is enabled will no longer work. The alarm will not tell you if you forgot any of those inside the car, with possibly tragic consequences. What's that? You say you have no children or pets? Just wait until ownership of the car passes to someone who does and the disconnect is traced right back to you by a lawyer.

If you google for "Land Rover LR2 Battery Drain" you'll see that the problem is almost always the satellite radio module. One way to diagnose is to try to use sat radio, and if it doesn't work, there's your sign. You can replace it if you use it, or disable/bypass it, your choice. You can probably find them relatively inexpensively at car-part.com (a website that centralizes searches of vehicle recyclers). The SDARS module is located in the rear Left Hand (LH) side of the luggage compartment. You get to it by removing the LH rear trim panel.

 

Everything you say is true, but completely irrelevant to me.
Also, you exaggerate the time it takes for the computer to sync, I insert the key, and by the time I press the start button, the car is ready to go. I have been running the solution for several months now with no problems at all.
Finally, regarding the alarm, the Land Rover alarm is a complete turd that will go off in the middle of the night for no reason, so that’s two birds with one stone. And yes, I’ve replaced the hood switch and had the dealer diagnose, no problems according to them.
I was at a point where I was either going to junk the truck, or find a permanent solution for the battery drain issue. I have an extensive list of parts that were replaced before jumping the gun, the satellite module being one of them.

 

You said it yourself, jumping the gun. I don't exaggerate anything, read the forum to verify what I said.

There are very few things in an LR2 that can drain the battery in a few hours, and some smart monitoring (not in the shop) can pinpoint the issue. I hope I don't run into your mechanics...

As to the hood switch, that *is* one of the things that can and should be bypassed.

Anyway, I'm out of here.

 

Let's be clear.

Your solution to effectively disconnect the battery after each use is clever.

However for anyone that needs to get their emissions checked this won't work.

The OBDII diagnostics have monitors https://www.deq.virginia.gov/Program...DMonitors.aspx

Every time you remove power from the Land Rover ECU the Monitors will be set to incomplete

Where I live incomplete monitors = fail

To reset the monitors typically takes a week or two (without removing power)


For my $$$$$ I would investigate the source of the parasitic drain, search for Voltage drop across fuses.

My LR2 can latch up one of the modules (see above satellite radio module) if the battery is old and the voltage dips too much during starting.

The latched up module will drain the battery.

To fix the problem I replace the battery every 4 or 5 years.

And my LR2 starts every time without hesitation for another 4 or 5 years.


Thanks for letting us know what you did.

Let us know if you fail your emissions check

Thanks

Paul

 

hi Paul, to your knowledge, is there a “how to“ to diagnose and disable the satellite radio? It’s something I would love to do, but I have no idea where to start...

 

I haven Disabled my satellite radio module yet so I don’t know for certain how to do it.

Here is my understanding of how the system works

A M.O.S.T RING (a fiber optic cable network) Is used for the entertainment system to connect the modules

If you disconnect the Fiber and you don’t connect a loop back then the Entertainment system will be disabled

Here is what I am going to do

1 Remove the fiber optic cable from the Satellite module

2 install a fiber optic loop back on the cable that I removed

3 disconnect the electrical connector from the module

to do this you will need one of these.


I did try to do this but I found the Bluetooth module instead of the Satellite module and it worked by doing exactly what I described above. The only problem was that it disabled the wrong module. I need to find out where the Satellite module is mounted. It’s somewhere in the trunk behind the trim panel.

 

most of what you said is above my head, unfortunately. But I will be asking some knowledgeable people questions, and will report back if I find anything interesting

 

This post has some pictures

look at what I wrote and the pictures I posted

https://www.freel2.com/forum/topic36724.html


Good Luck

Paul