Operating The Transmitter Unlock Switch Press Twice
WARNING: This page is about a different car, the 2005 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.
When the transmitter unlock switch is pressed twice, the ETACS-ECU energizes its door unlock relay to operate the driver's door lock actuator and the other door lock actuators for 0.25 seconds each in succession. Then, the doors will be unlocked.