The technology used in older model (pre-2000 era) Genie garage door systems utilized a series of "dip switches" to regulate the actual frequency of the garage door wireless transmitter. Subsequent Genie models utilize a "smart" system to synchronize the garage door transmitter with the hand held receiver, with a constantly changing frequency. If you still use an older model, it is easy to change the frequency on both the transmitter and hand held receiver so that they synchronize, enabling you to remotely control the door's operation.
Unlock the garage side door or other entrance to the garage so that you do not inadvertently become locked out of your own garage. Open the garage door manually by pulling the emergency release handle located between the garage door and the garage door motor (mounted on the ceiling). The handle will be midway between the two garage door tracks. Pull the handle straight toward the ground.
Raise the garage door manually to the full up position, so that the garage door is open. Place a step ladder directly below the garage door motor. Climb the ladder and open the plastic inspection panel located on either the front or back of the unit, by releasing the plastic tabs.
Locate the "dip switches" which will appear on one side of the control board, directly beneath the plastic cover you just removed. Grab a flashlight, and inspect the position of the "dip switches". There will be 12 of them in a row, forming a sort of pattern such as "up," "down," "up," "up." Write down this exact pattern on paper. Double check to make sure you have it correct, then climb to the ground.
Open the back of your Genie garage door transmitter using a coin to unsnap the plastic tabs holding it together. Most transmitters have a slot on one end for just this purpose. Remove the back cover of the transmitter. You will see a similar set of 12 "dip switches."
Align the 12 "dip switches" in exactly the same pattern as you have written on paper. Double check it to make sure it is correct. Snap the cover back on the back of the transmitter. Test the operation of the garage door using the transmitter. If you got the "dip switch" positioning correct, the garage door motor will turn on. After it stops moving, return the safety release cord to it's normal position.