My pocket was always mysteriously opening my trunk. After a bit of thought, I realized this was because my keys were in there and hitting the trunk open button on my key fob.
I tend not to use my key fob to open my trunk that much. After looking through my manual I couldn't find a way to disable the key fob button to open the trunk and keep the button in the cabin working. I suppose going into the car's computer could do it, but I'm not the computer hacking type.
What I have here is a simple, fast and easy, fully reversible way to disable any button on a key fob.
My car is a GM, I know other brands use a similar system, but your car may vary.
Materials: Little bit of plastic bagging
Tools: Scissors, coin, brain, hands.
Step 1: Theory
I don't like magic. If you know electric theory at all, you probably won't need to know this. But if you don't, this will demystify it.
The buttons on a key fob work by having a conductive pad touch an open circuit on the Printed Circuit Board (PCB) and therefore close it. All that has to be done is stop the circuit from completing. We need an insulator between them to disable the button.
Step 2: Disassembly
These things are made to be dissembled to get to the battery. All you have to do is crack it open with a coin, I used my house key, at the wide spot. Pull out the rubber buttons and circuit board, the pull the PCB out of the buttons. Takes about thirty seconds.
Step 3: Cut and Place
Use a small bit of plastic sheet, like from a bag, and cut it to be big enough to cover the pad and stay in place, but small enough to fit in the button.
Then simply place it on the conductive pad of the button you wish to put to sleep.
Undoing the whole project just involves the reverse of this step, take the plastic out and make it part of the bag it came from. Or just the first part of that sentence.
Step 4: Put It Back Together
Just orient the board and the buttons, seat the board, seat the buttons, then snap the back on and you're done. Took me about 3 minutes to do as a whole.