I really like when all of my doors open without having press the button twice. I have a 2011 double cab with the dealer "carr" alarm.
With the truck running in park.
Press the door lock button on the driver door.
Press the door unlock button on the driver door twice.
To test. Turn off truck. Lock door with remote. Then press unlock with the remote. All doors should unlock at the same time.
Please post up if this works for your year and cab model. Also please specify if it has a dealer alarm or not.