Residential garage door opener remote transmitters operate your automatic garage door using a radio frequency signal. The radio frequency that is used may vary by garage door opener brand and model. Examine the back of your remote transmitter to determine which frequency it uses; Homelink can only be programmed to control devices that operate between 288-433MHz. If your garage door opener doesn't operate between 288-433MHz, you can't program Homelink to control it.
If the battery in your remote transmitter is weak, the transmitter can't send a strong signal to Homelink, which can make the programming process much more difficult. Homelink recommends replacing the battery in your garage door opener remote transmitter before you begin the programming process. Consult your owner's manual or contact your garage door opener's manufacturer to obtain battery replacement advice if necessary.
When programming Homelink, you must hold the remote transmitter the appropriate distance from the Homelink console. Homelink's "Getting Started with Homelink" guide recommends holding the remote transmitter between 1 and 3 inches from the Homelink buttons on your visor or overhead console. If you continue to experience problems, Homelink recommends increasing the distance to 4 to 6 inches and varying the angle of the remote transmitter.
During the programming process, your remote transmitter may suddenly stop transmitting its radio frequency signal even if you are holding the button down continuously. Cycle the remote transmitter while programming Homelink to prevent this from happening. While holding down the Homelink buttons, press and release the button on the remote transmitter every two seconds. Release the Homelink buttons and stop cycling the remote transmitter when the Homelink indicator light begins flashing rapidly.