Here are some items to check. Limited range of your remote controls could be related to radio frequency interference that comes from something in your home or in the surrounding environment. Certain electrical devices can radiate interference; this could be almost anything that is plugged into an electrical outlet. Please keep in mind that the device can be brand new, or can be an item that has been in use for quite a while. Also, the item may continue to function properly as far as you are able to tell. The only problem with the item may be that it has started to broadcast the interference, with no other symptoms noted. Some devices are more likely to generate interference than others. This includes TV cable, cable amplifiers, surge protectors, fluorescent lights, battery charging devices (power tools, golf carts, etc.), anything that utilizes a timer (sprinkler systems, lights, alarm systems, etc.), and a myriad of others. If the problem seems sporadic, we can safely assume that the device responsible for the interference is only being operated during these times. Again, please keep in mind that the age of the device does not determine if it is capable of broadcasting unwanted interference. Any electrical device can be the source of the problem. The first step is replacing the battery in your remote. If the range on your remote does not improve, remove the wall control wires from the overhead unit. If the range does not improve you will likely need to replace the remote control. After replacing the remote, or if you have other remotes programmed in to the opener, and the range problem still exists, please proceed to the Power Down test. Multiple garage doors: If you have two garage door units and one is working just fine, you will need to start by unplugging the good unit. This will help determine if the unit with no range starts to function properly. If the range comes back to the bad unit then you will need to replace the logic board on the unit that was unplugged as it is emitting an RF signal that is over powering the other garage door opener. If the range doesn not improve after the "good" unit has been unplugged, replace the batteries and try programming some additional remotes to determine if the existing remotes are the issue. If the extra remotes do not have any range then you would need to replace the receiver logic board in the "bad" unit. Power Down test: To isolate potential sources of interference, turn the circuit breaker off to the garage and plug the garage door opener into an extension cord from another room. If the range improves, then the interference is coming from a device in the garage. If no improvement is seen follow the same procedure, this time turning off the circuit breakers to your home, with the exception of the garage and test the remote controls. If improvement is noted, turn the circuit breakers back on, one by one, until the range problem resurfaces. This will allow you to narrow down what room the problem device is in. You will have to go from there to isolate it further, by unplugging and re-plugging the items in that room. If you are unable to determine any source of interference, then the receiver logic board in the overhead unit will need to be replaced.

We had a similar problem and the fix was simply aligning the sensors. It is so easy for them to get bumped out of alignment.

For everyone having the problem with your garage door not closing... I've read this entire blog and tried everything suggested. The force/travel adjustments would solve my problem for a while then it would come back so, if you've already checked sensors, wiring for damage/connection, adjusted the up/down force, adjusted the up/down travel here's something to try before buying a new opener: Inside the unit find the up/down travel adjustment mechanism(see photo). At the end opposite the screw-heads you turn to adjust the travel there is a gear mechanism. When these gears wear they can slip. In addition, the chassis for the gears is plastic and over time will weaken-my opener is almost 12 years old! My gears are still in pretty good shape. The problem is that the chassis would flex and allow the gears to jump hence, the reason my adjustments would work for a while then the problem would come back. Now I know this will sound like a hokey fix but I figure it is better than dropping a couple hundred bucks on a new opener...I pushed a toothpick into the hole in the main chassis where the travel mechanism is snapped in essentially eliminating the chassis from flexing and allowing the gears to slip. make sure you do this on the side opposite the gears. If you do it on the same side you will put a larger space between the gears making the problem worse. This has been working for nearly a month now. I attached a picture of the travel adjust mechanism for reference. It is difficult to see the toothpick in the photo. It is right next to the brown wire connection opposite end of the mechanism from the adjustment screw heads. One other hint: the opener will most likely get hot running the door up and down making your adjustments and will shut off (thermal overload protection). I don't know why but after this happened the green light next to the remote programming button on the back would flash 5 times-off-flash 5 times...repeatedly. I had to pull the power for a couple minutes to get the light to stop blinking. Either let the unit cool for about 10 minutes after it shuts off or to keep your unit from overheating, place a small floor fan in position to blow on the motor. Craftsman 1/2 HP model# 139.53971SRT manufacture date: 02/2000

Can you send some good pictures of controlling factors or concerns? I have a number of 1980's Craftsman Door Openers I still use. I have seen, installed and adjusted a few others different in the way they operate. Age and plastic wear can be a factor. 1. Do you have switches on the track controlling the door or contacts in the by the motor? 2. I’m saying switch’s screws could be worn or broken and reacting different with force. 3. If door’s engagement guide travel further disengaged, resistance is detected somewhere or “faulty Mechanics”. Ck all plastic parts, adjustment screws at that point. 4. Oil all moving parts with recommended oil in manual (all wheels, track/trolley and plastic “Worn Worm Gear”. 5. The chain is usually spring loaded with centering adjustments to allow the spring to control the tension. Good Luck!