It uses the same one for the Power Door locks.
You did not specify that you are doing this to the 5-doord hatchback or the 4-door sedan - so we're guessing...
Some of us whom own a hatchback, still call it "trunk"
So if you can use the key fob to unlock the doors and yet the rear hatch won't open using the keyfob.
And...
The rear release button on the rear hatch cowl panel above the license plate won't open the rear hatch or trunk.
IF those conditions fail...
IF you have the sedan, 4-door - you'll have to open and unfold the rear passenger seats and check the condition of the rear hatch internal release - if it's been damaged or not properly seated, this can prevent the relay and switch from operating and unlatching the catch - because the catch is stuck due to that emergency pull handle is not letting the catch properly seat itself.
![1721576921092.png](/data/attachments/9/9462-18efa1a41d4f74f3763fe594de28cf0f.jpg)
In the Hatchback, the process doesn't have an emergency pull handle - but it is a good idea to see if placing your hand on the rear panel and pushing down while operating either the button or the keyfob - and seeing if releasing some tension on the catch can help make the system move that latch so you can open it - this pressing down effort might help.
Once it's opened - see if the catch part, the one on the body side - not the hatch, is stuck or pressed in and down preventing the catch on the hatch side from having some movement to release the catch when the relay operates - the seal on the lip of that lid (Body side seal) can also prevent the latch and catch from operating because the seal is binding the catch and latch together.
You may need - by using TORX wrench - loosen the catch (Body side fixed latch) so the rear hatch can be then re-seated and the catch and latch are not binding together - and reset / reseat the latch bolts once there's enough space for slack and take the tension the seal can put on it, taken off of it to help the catch release from the latch.