Garage doors are heavy and can injure children and pets. Sears Craftsman garage door openers have an important safety feature that prevents the door from closing when something or someone is in the way. This safety reversing sensor is actually a pair of electric eyes that generate and receive a light signal that must remain unbroken for the door to operate. If it's interrupted while the door is closing, the door reverses and a safety light on the opener flashes 10 times. The Safety Sensors The installation instructions for a Craftsman door opener call for installing the sensors 6 inches above the floor, and you can mount them to the floor, the wall or the door track with the brackets provided. If they are properly aligned, both sensors display a steady light; the one on the receiving sensor is green and the one on the sending sensor is orange. If something is in the path of the beam or the sensors are misaligned, it's typically the green light on the receiving sensor that flashes. When the orange light on the sending sensor flashes or stays off, it usually indicates a loose wiring connection.
Stuff in the Way The most common cause of sensor malfunction is also the easiest to remedy: Something is blocking the beam. It may be a garden tool or something left behind by children, such as a wagon or beach ball. If your garage door has been in place long enough, enough dirt may have formed on the lenses to block the beam, or cobwebs might be in the way. When this happens, the green light on the receiving sensor flashes or it stays off altogether. The orange light on the sending sensor will remain unaffected and be glowing steadily. Misalignment or Loose Wires The green indicator light on the receiving sensor also flashes or fails to illuminate when the sensor is out of alignment with the sending sensor. You can often restore alignment without tools; simply loosen the wing nut holding the sending sensor to its galvanized steel mounting bracket and adjust its orientation until the green light on the receiving sensor glows steadily, then tighten the nut. If the orange indicator light on the sending sensor is off, it usually indicates a bad electrical connection.
Check the connection to the sensor and follow the wire all the way to the terminal on the back of the opener. You might find a staple or nail cutting through the wire insulation. Light Interference Some sensors temporarily malfunction at certain times of the day, and the problem is related to the angle of the sun. If the sun falls squarely on the receiving sensor, it can fail to detect the light beam generated by the other sensor. To remedy this, you might have to construct a guard around the sensor to block sunlight; an empty paper towel roll works well for this. Cut about 2 inches from the end of the roll and tape it to the sensor with duct tape to restore sensor operation. References Sears Parts Direct: Craftsman Garage Door OpenerSpokane Garage Repair: Common Garage Door Opener Problem -- Safety Eyes Photo Credits Jupiterimages/liquidlibrary/Getty Images Suggest a CorrectionThis post pertains to anyone having issues with their Craftsman, Chamberlain, Liftmaster, or Sears automatic garage door openers due to apparent photo sensor problems.
I myself have a Craftsman automatic opener with sensors that look very much like the ones in the photo below. However, one noticeable difference is where the wires connect to the sensor casing. On my original sensors, there is a white rectangular connector that slides onto 2 pins that stick out of the back of each sensor. Aside from that, everything else appears to be identical to the replacement Liftmaster Sensors Part # 41A4373A I had taken a little different approach this year and did my research to find that this is a very common problem when dealing with these sensors and in most cases the cause is simply that the sensors are going bad and not because the became misaligned. e41A4373A) part number I had listed above. If your sensors have a green light on one and amber/red light on the other, then you would want to purchase part # 41A5034.How do I test or troubleshoot the safety reversing sensors? The safety reversing sensors must be connected and aligned correctly before the garage door opener will move in the down direction.
Typically issues with the safety sensor wiring occur because of a poor connection, incorrectly connected wires, or a short in the wire from a staple. NOTE: If you are unable to get the door closed and the safety sensors are the issue, the garage door can be closed by pressing and holding the Door Control push bar until down travel is completed. If both safety sensor LED lights are not lit Security+ 2.0 garage door openers have an energy conservation feature. If the garage door opener is Security+ 2.0, have the customer activate the door to determine if the opener was only in sleep mode. See Security+ 2.0 energy conservation feature Check for incorrect wiring between the sensors and the garage door opener. Verify the wire connections are correct on the garage door opener. The solid white wires connect (insert) to the white terminal (2) and the white/black wires connect to the grey terminal (3). NOTE: The amber LED on the sending sensor will glow regardless of alignment or obstruction.
If the green LED on the receiving sensor is off, dim, or flickering (and the invisible light beam path is not obstructed), alignment is required. See How do I align my safety reversing sensors? Test the safety sensor wires. Remove the sensors from the brackets. Remove the wires from the wire nuts or cut the sensor wires 12" from the sensors. Strip both ends of wires from each sensor and twist like colored wires together. Proceed with both sensors to the garage door opener motor unit. Remove existing wires from the white and grey terminals on the back of the operator. Attach or insert white wires into the white terminal and black/white striped wires into the grey terminal. Point the sensors at each other - if both sensor LED's turn on, there is an issue with your wiring. Replace the wires between the opener and the sensors. If the LED’s DO NOT turn on, replace the sensors. Note: If after replacing the sensors, the LED's still do not light, replace the logic board.