O,
I'm a little confused what you are asking so I'll go in the order you wrote. The trunk switch on the trunk itself is under the lip and on the right side of the trunk, not in the middle like one would expect. You say both the trunk button on the dash and on the remote work then you say the switch (I assume you mean the one on the trunk lid itself since the dash one works) is new and has new looking wires. So this statement would be lead me to believe you do know where the trunk lid switch is...? Your last sentence says the dash button for the gas door has never worked. I don't know how this is possible as it's the only way to get that door open to put gas in your car.
Reading it all several more times, maybe you're saying the trunk lid switch on the trunk itself is not working? Yet the trunk does open from the other switches so that would seem like the switch on the trunk lid is not connected somehow since it is new (assuming that was the one you were talking about). So maybe it's not plugged into the harness further inside the trunk? Obviously the electromechanical trunk release mechanism is plugged in and works so it's not related to this problem...if I'm understanding you correctly. I would check for voltage at the switch. Others on here have access to the electrical drawings for our cars and it would be helpful if you had the drawings for that switch to know what you are looking for electrically.
