Dead battery

The simple easy way is to plug into the cigarette lighter / power portwith a cord for charging, you might have to buy the necessary USB to 9v battery connector or create your own. Another method is to use a battery jump-pack and use its power port to connect directly to your LS's power port, all you need is the correct cable.

Use the key to open the trunk.

@bob I would have if that actually worked...have you owned one of these cars before?

@auto_centric thanks for the info! But I figured another simple way to get a charge long enough to pop the trunk.

Holly, Perhaps I wrongfully assumed that there was a trunk key similar to my Mercury Marauder. Is there a key or did it just not work?

@bob I'm uncertain if there is an actual trunk key for this car, but I did end up getting in the trunk! Now, 5 months later, I've ended up closing the trunk with the battery unhooked like an idiot...I'm currently searching for a way in that does not require electricity :( there is no pull lever inside of the car to get in from behind the seat either...stupid, stupid car.

Holly, through the back seat.. the bottom part of the seat comes out when you apply pressure to the edge and pull forward either on the seat or a pull cord located just under the seat. Out will be sticking out. Then using a14 or 13 mm socket. Loosen the two bolts located on the bottom of the top part of the seat.. lift up and pull at the same time.. goo through the back seat compartment and pull the safety latch to the trunk..

I have a 05 v8 ultimate Lincoln ls and have constant battery draining problems and holly the key WILL work to open your trunk without any power i can assure this because i was freaking out first time it happened and the button didn't work either and then i decided to try my key and lone behold it worked and still does

My lincoln doesn't have a key hole on its trunk....am i just not seeing it????

There is an emergency key slot at the back of the car on the right side there's a small little hole stick the key in there