Verified answer

you may have a bad sensor

Need more information:

1) Can you disconnect the opener and open/close the garage door manually? If not then you have issues with your garage door and not the opener.

2) If yes assuming a 7' high door with four sections can you leave the door 1/3, 1/2, and 2/3 open without it going up or down by itself? If not then you need to balance the door and will need a garage door company to do so for you.

3) If yes will your wired wall switch open the door? If not then lube the hinges with wd40 and possibly increase the up force adjustment. If you still have problems then you'll have to call a garage door company.

4) If yes can you close the door by holding down on the wall switch until the door quits moving? If not then lube the hinges on the door with WD40 and possibly increase the down force on the opener. If you are still having problems you'll have to call a garage door company.

5) If yes will your wireless transmitters open the door? If not then there is a problem with your transmitters. Check to see if they cause the lights on the motor head to go on. If not then maybe you have interference, a bad receiver, or highly unlikely two bad batteries. If it's not a battery problem call a garage door company.

6) If yes to all of the above then check to see if the red light stays on all of the time while the door is trying to close. The door may be vibrating the sensors on the way down causing them to be misaligned for a brief second. Or it could be a wiring short. Try hot-wiring the safety sensors so they are in each others face. If that still does not consistently allow the door to close then you have a short in the wiring. Call for help. If the door does go all of the way down then slowly space them out until they are on each side of the door.

Problem solved.

Ric sounds like the sensors are working right,one should red and the other green,you didn't say what your garage door was doing so i don't know how to help,when your door comes down and the sensors are block and blinking the door will go back up,you may have another problem with the opener,hope this helps.

Both sensors should be green. If one is red the alignment be off, you may have a bad or loose connection or your sensor is shot.

the two might properly be properly matched using an identical distant. visit residing house Depot or Lowe's with the variety # of the Liftmaster and notice in the event that they sell a separate distant.they could even have the potential to tell you if Liftmaster and Craftsman greater healthy.

Does the wall switch work? if so then your batteries are dead or you need to reset the code for the remotes.

Change the batteries in the remote.