I got a problem with my garage opener in past few days. I can close the door when I leave for work but cannot open the door when I come home. At first I thought the trouble is caused by cold weather. Then I thought is the board gone bad. However, when I get the remote close to the antena, everything works fine. Finally I observe that my garage door open/close indicater(Made by Craftsman) both lights are flashing(red and green). Therefore I disconnet the AC power on the receiver then test out the garage door remote. Surprisely, everything works like a charm. The trouble is caused by the unit that attached to the garage door runs out the battery. I bet the receiver unit was sending signal to find the door unit consistenly which interferences the signal of garage door remote control, including my keypad door opener. After I replace the battery on the door unit, everything is back to normal. Just want to share with anyone who has the same situation. Signal interference will cause the trouble to remote control.

Hi everyone, I know i sound like a tape recorder but my craftsman 1/2 hp has been working fine for 3 yrs. Not sure what happened to the remotes, but they stopped working. I first tried replacing the batteries but after that didnt work i went out and brought two brand new up to date chamberlain klik3u universal garage remotes. Retail 40 bucks per. They say in the manual they are compatible to my garage opener which was manufactured in 1997. They wont program as well. My garage opens and closes fine. I guess im here to find out if anyone has any other trouble shooting facts to program because the "press the red button like a door bell, hit the button you want programmed" basics isnt working for me. I called chamberlain about the remotes and they basically told me go jump in a lake, all our remotes program fast and easy!!! I need help ppl. Plzzzzz

Following the (minimal) instructions in the manual, I connected the sensors on BLACK and WHITE screws, in parallel. The SEND one is constant green, and the receiver side is green unless the path is obstructed, then it goes out. So alignment and wiring all appear to be 100% correct. The problem is the door ALWAYS closes even if the path is obstructed. It doesn't stop closing, or blink- just behaves the same as when there are no sensors connected! I'm not sure what to test now?

What kind of Garage Door Motor do you have?