My craftsman 139.18405D doesn't always stop the door at upper or lower position I've set up (I set it up in strong accordance with instructions in Manual) . In most cases, it goes beyond the upper point I set (usually hitting the stop bolt) when it opens and it doesn't reach the lower position when it closes. And it's unpredictable at what particular position it will stop next time I click the button to open or close it. One time it can stop at 5-6 inches above the ground, next time this distance can change to 2 inches, next time it can stop at ground, and next time it can stop at 7-8 inches. And I've also noticed that in winter time it's more predictable and more often stops at positions I set. Summer time it's much more unpredictable. Sounds crazy? But that what I've noticed. I am tired of setting up those positions once and once again. The door itself is well installed well and well balanced. It goes smoothly all the way up and down. When it's disconnected from the trolley I easily can open or close it with one left hand (it is a wide door - for two-car garage). Once I've disassembled the motor part and have visually verified the logic board (part # 41DB102-2), the motor (part # # 41D843) and didn't see any suspicion places. Everything looks good. While assembling it back I made sure all contacts are good in all internal plugs. This didn't help. It keeps working just the same unpredictable way. By the way, I can often notice the yellow indicator above purple and black buttons is blinking 13 times then switches off for half a minute or so and then blinks 13 times again. And this indication is not mentioned in Troubleshooting section in Manual. Has anybody ever seen this kind of issue? What can be the reason?