Using the 12v trunk plug without cutting out after 3 minutes?

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machmike

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I was out using my telescope in the mountains and needed to use the 12v accessory plug located in the rear of the truck near the tailgate after my portable power supply died. The 12v plug would only stay powered for 3 minutes at a time before the truck shut it off. Is there a way to keep this from happening without having the truck running?
 

cperez

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There's a relay in the fusebox that needs to be modified. It is explained in this post but unfortunately the photos didn't load for me:

https://www.landroverworld.org/posts/150760/

Hopefully it will lead you in the right direction at least. The main caveat would be to be aware of the reserve in your Rover's battery. It doesn't seem to take much to get a low battery warning. If the device can be run from a USB power bank that would be better than taking a chance. Or make sure you have a good boost battery on board for jumping the Rover if necessary.

Edit: Sorry, you did say that you were trying this after your portable supply died. I missed that. Same caveats above still hold, however.
 

machmike

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As always thanks for pointing me in the right direction.
 

CharlesZig

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Thanks for the welcome, AGoodStory The search function you have pointed out is definitely much better than the site search. In combination with google Im sure Ill be able to find everything I need
 

toddjb122

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This is an awesome tip and reminder. Thanks.

One of the most annoying features of the LR3/LR4 for me is the lack of any usable DC power when the truck is turned off. You can't even trickle charge a cell phone like you can in virtually every other car.

That said, something about the rover electronics design has it chewing up a lot of power any time Accessory is turned on. So, even with it turned off (does this mod work with nothing turned on in the rover?) I still get a Low Battery warning way to soon in this truck.

Its pretty much the only reason I have ever wanted to do the 2nd battery mod... but man that seems like a lot of work just to be able to charge a phone. And you still wouldn't be able to run the car stereo for long when tailgating, which is another missed feature.
 

cperez

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I still get a Low Battery warning way to soon in this truck.

Given how much apparent vampire current is sucked out of these vehicles, I have come to view the power port shutdown interval as a feature and not a bug. Whenever I'm doing anything where the doors or hatch are open for prolonged period I'll just save myself the anxiety and manually turn off the dome lights before they go off automatically. It's not often enough that I need to enable "hunter mode" for those lights, but I do think about it.

Pocket USB powerbanks and good Bluetooth speakers have been my solution. We can't be expected to tailgate without music. We're not animals, Land Rover.
 

bbyer

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You don't need to mod the relay. Just remove it, and make up a 3 inch or so jumper using male spade connectors on each end.
The jpg attached is the glove compartment fuse box in my 2005 LR3 HSE; the LR4 may be different.

The red conductor jumper location located above the two lower small relays is the location of the "big" relay that I removed and replaced with the jumper.

That was many years ago and nothing bad has happened since other than some of my power sockets now remain powered 7/24/365.

If I recall correctly, the fuses that protect the sockets are still in the circuit as they are located down circuit of the relay.

Passenger Side Fuse panel removed dsc01807ck.jpg LR3 CJB Relay R1 jumper permanent aux sockets.jpg

The other jpg shows the glove box fuse panel with the big original relay in place.
 

toddjb122

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...The red conductor jumper location located above the two lower small relays is the location of the "big" relay that I removed and replaced with the jumper.

That was many years ago and nothing bad has happened since other than some of my power sockets now remain powered 7/24/365. ...

Some? I guess the LR4 may be different. Curious which ones are now constant power.

So, I am guessing that if I do this I just have to be responsible and not leave a power sucking device attached that'll drain your battery. BUT, leaving a cell phone connected, for instance, would not be a concern.

THANK YOU for sharing the photo.
 

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