11.2b If the springs you installed are too strong, and if you wind the springs the correct number of turns, the door will not stay down nor half way. The garage door will be hard to close. DO NOT REMOVE MORE THAN HALF A TURN OF SPRING TENSION TO CORRECT THE PROBLEM. Here's why. If you remove 3/4 of a turn to get the door to stay closed, and then if you open the door, it will get heavier as you open the door, and once open, the cables will come off the drums. This could create as much as a day's extra work. It could also cause door damage and/or result in serious injury. Do not use the door! Get different springs!
If your photo eyes are clean and the door still isn’t closing, the next thing you’ll need to do is check the alignment of the eyes. The eyes should be pointing in exactly the same direction and at the same angle. If they’re off, they won’t register that the other one is there, and it’ll assume something is in its path, causing the door to stay in the open position. When checking the alignment, measure the height of each photo eye from the ground. Use a level to make sure they’re pointing directly across at each other at the same angle. A laser level will make this part a little easier, but if you don’t have one, a regular level will work as well. https://www.youtube.com/embed/Z_eZc-kh40c
When you know you’re in range and the door still won’t open, check to make sure the antenna is hanging down from the motor inside your garage and nothing is blocking it. Your antenna must be free from any obstruction to clearly receive the signal to open and close the door. Also inspect the antenna for any signs of damage. If it looks like there has been damage to the antenna, you’ll need to call your garage door technician to come out and replace it.
With over 300 independently moving parts, your garage door is a deceptively complex piece of equipment. To help prevent malfunctions and break-downs, it is a good idea to occasionally perform a garage door tune-up to keep all of these parts in good working order. A regular tune-up service by a Sears professional can prevent unexpected door problems and prolong the life of your existing equipment. http://m.youtu.be/Z_eZc-kh40c