I have tried to change the automatic door lock feature from Mode 1 (default from factory) to Mode 2, which is the doors lock after reaching 12 mph, but have had no luck. I have followed all the steps as outlined in the owner's manual to do this.

Anybody out there has had success changing these modes?

 

The following steps to program the Sequoia door looks to automatically lock at 12mph, works for 2002 Sequoia's. However for the 2001 models the dealer must perform the programming using a hand-held tester plugged into the OBDII port. This function is the Auto Door Locking function.
1. Set the parking brake, close all doors and turn the ignition to the ON position.
2. Shift the selector lever from the "P" to the "N" position.
3. Press the driver side power door lock switch on the "front side" for about 5 seconds,
within 10 seconds after the ignition switch is turned to the "ON" position.
4. the doors will be locked and unlocked to indicate that the function is set.

To cancel the setting, repeat the process above.