 Owner's manual...
The procedure is in the owner's manual. From page 112:
Programming a personal entry code
Up to three personal entry codes may be programmed to the vehicle. To create your own personal entry code:
1. Enter the factory set code.
2. Within five seconds press the 1 • 2 on the keypad.
3. Enter your personal 5-digit code. Each number must be entered within five
seconds of each other.
4. Press 1 • 2, 3 • 4 or 5 • 6 to indicate which of the three personal entry
code positions you wish to use.
5. The doors will again lock then unlock to confirm that your personal key
code has been programmed to the module.
The factory preset code will work even though you have programmed a new one. If you lose power (e.g., battery goes dead), then only the factory preset code will work and you will have to reprogram a new one. | 
