I must installed a 1/2 horsepower chain-drive Craftsman garage door opener. It is a 'new generation' unit so I had to replace all the remotes. My problem is that it will open on its own! I have remotes in two vehicles and one in the house (I have not been able to program my built-in controller in my 2009 Toyota, so I have a Sears remote clipped to the visor). It will remain closed for an extended period and then open on its own. There is no apparent cause and I don't believe it is interference from another remote in the vicinity of our house. Any ideas?

Here is some info that may help you. Make sure you don't have a broken spring or cable. For Side Mounted Springs Only... You must release the tension on the garage door springs before attempting adjustment or replacement. This is accomplished by opening the garage door as fully as possible until it hits the stop bolt on the track. Hold the garage door in this position by attaching a C-clamp to the track at a point below the lowest door roller (wheel). This is true even if you have a garage door opener. Just because the door is open does not mean that the spring tension is fully released. Use the emergency release rope to disconnect the opener from the door and push the door up as far as you can without damaging the opener. Then clamp as described above. If there are safety cables installed, they must be disconnected and removed from the springs. The old spring is attached at two points. One end is a fixed attachment to the garage door track or wood frame. The other end is attached to a pulley through which the garage door cable is threaded. Simply disconnect these two attachments and reattach the new spring in the same way. Be sure not to twist the garage door cable when reattaching the pulley. While the pulley is disconnected from the spring, give it a quick hard look. If it appears that the pulley bearings are very sloppy and have lots of wobble, replace the pulleys. There is no repair other than replacement. The door will function more smoothly and save you additional work later. And you might as well check the stationary pulleys, too, while you are at it! Makes sense, right? Once all attachments are completed, test the door once for proper function before reattaching the safety cables. You may find that the new springs may be too "lively" and the door may not close all the way. If that is the case, you will have to look at the way the bare end of the garage door cable is attached to the garage door track, and loosen an inch or two. This end may be simply looped through the holes in the track, or it could be attached by means of a special clip and an S-hook. In either case adjust both sides equally either by shortening the cable or by repositioning the S-hook in a different hole in the track. The springs should visually be in about the same position when extended fully (door in down position). Of course, if you do not have enough tension in the springs, and want to make manual opening of the door easier, you may adjust the garage door cable into a tighter position also.

I figured it out. Problem with adjusting the limit switches was due to a missing pin on a gear that is on the main motor shaft that turns another gear that moves a plastic screw that hits the up and down limit switches. In other words, the internal up/down limit switches were not getting consistant feedback of the garage door position. Nothing that a twisty tie from a garbage bag couldn't fix. So that problem was fixed. The garage door now moves and it now moves up and down without whacking the header going down and the stop limit bolt (protecting the GDO motor unit) on the way up. I knew I was wasting time when the manual says a single rotation on either screw would result in a 2 inch travel change. and nothing I did was consistant. It either hit the bolt or header or it would just HUM and not do anything. I think the original problem of why the belt's tention spring/bolt came undone was due to excessive vibration due to non-sufficient belt tension. As soon as i got the garage door operational, I noticed it was hecka jerky initially going up or initially going down. Mid-travel was smoother. By tightening the nut (collapsing the tension spring) to the 1.25 inches specified in the owners manual seemed to make the garage door much smoother. When I have the time, I'll adjust the force screws down. I think I have them maxxed out right now. I'll also test the safety/reversing feature. For now, it open and closes smoothly. I'm happy. So, while the owners manual didn't tell me to open the thing up, common sense told me to. Also, this unit has a diagnostic feature. When you press the LEARN button, it will light up the diagnostic light and blink. 5 blinks told me the motor was overheated or the RPM sensor wasn't happy. No mention of what the RPM sensor was. I'm assuming something was stuck. Anyways, adjusting the limit switches got it moving and once I cracked open the motor housing case and saw the limit switches in action and saw how misaligned they were, it was a pretty easy fix. Glad I disconnected the door so I could cycle the belt for testing without crashing the door. that made way too much noise at 10PM tonight. Once again, thanks for your help and I hope something in this helps someone.

amasake, I spent (wasted) seven years with someone that didn't 'love' me but let me raise his children. (he wasn't all that interested in raising them himself) He was more concerned with what he needed, than what I or even his kids needed. After I left (and he gave up after a year of trying to get me back), he married the next girl that came around. His kids were entering their teens then and his wife didn't want anything to do with his kids. She had her own and then got him to have two more with her (twins). His kids pretty much raised themselves and left home as soon as they could. One of my biggest regrets is leaving before the kids were grown or not maintaining a relationship with them. The only choice I had to maintain the relationship with them was to go back to their dad. I was the only mom that 'mothered' them. If you were to say you have a relationship with his son, I would tell you to think about that before leaving, but it doesn't sound that way. My point? What I would say is that you can't fix someone else's problems. It's not even a matter of whether he loves you or not. He sounds too focused on himself that he doesn't see what his son needs anymore than he sees what you need. I feel very sorry for his son because it sounds like he's given up on his parents and just wants to get old enough to escape the hell they have created for him. (just like my ex's kids) The worst feeling I've ever had was to wake up at 29 and realize I wasted my 20's, raising six kids and being with someone that didn't love or appreciate me. (I was 22 when we got together & I had 3 kids plus his 3)