Open the cover of your GTO remote transmitter. Grasp the sides of the remote with one hand and squeeze down on the center of the cover with your other hand to slide it downward.
Look for the internal DIP switches inside the remote. These are nine numbered slots. Each slot will have a toggle switch that can be moved toward a (+) sign or a (-) sign.
Create your remote code by choosing a series of (+) or (-) positions for each slot. For example, toggle the slot designated as "one" to the (+) position to indicate that your code begins with the number one. Toggle the slot designated as "two" to the (-) position to indicate that the code does not include the number two. Continue with your choices to create a code. For instance, your code could be "1-3-5-8-9" by choosing the appropriate slots and (+) or (-) combinations. Make note of this code then close the remote.
Turn off the Mighty Mule keypad. This requires accessing the control panel that was installed when your system was set up. On the outside of the control panel at the bottom, there is a small black "On/Off" switch. Turn the switch "Off" and the keypad will be disengaged.
Open the control panel by removing the screws on the panel. You will see the inner circuit board. Look to the lower right-hand corner of the board for a button labeled "Learn."
Push and hold down the "Learn" button while simultaneously turning on the black "On/Off" switch. Release the "Learn" button once the switch is turned to the "On" position.
Look in the upper left-hand corner of the control panel. There will be a red glass tube marked "Status." Push and hold down the center button on the remote. When the status tube glows red, the remote is synched with the keypad. You can now use the remote to open the gate or use the keypad by entering the code you created. Close the control panel to complete the sync process.