HBW0777 Sears / Craftsman 1/2 HP Chain Drive Garage Door Opener

Problem: Neither of the remotes work but the manual button bar (the wired one in the garage) and also the keypad operate normally. The green LED behind the manual button bar flashes. The batteries in the remotes are fresh.

Fix: Get on a step ladder and press the green button up in the center rear of the motor housing. I couldn't dig up the manual but I believe that the system is in a secure 'lock' mode which disables the remote sensor for use at times when you will be away from home for a long period.  It is possible that someone pressed a combination of buttons on the remotes and caused this, or that holding the manual button for a certain period of time enables lock mode, but I don't have the manual and could not locate it on-line and the buttons on the remotes do not have any labels on them.

Other problems I've had:  Door reverses direction in the middle of closing. If the motor runs too fast and causes some binding when the door reaches the arc of the tracks, the system reads this as an obstruction and reverses. Solution 1: There are two slotted adjustment ports (they look like plastic screws) in rear right-hand side of the motor housing. These allow you to adjust the speed of the motor, one adjusts opening speed and one adjusts closing speed.  Fix: Slow down the motor on the closing side.  Solution 2: It is also possible that the optical sensors are out-of-adjustment and need to be re-aimed.  It is possible that the tracks are loose or mis-aligned.  One or both of the optical sensors may need to be re-aligned up or down.

System Details: Sears/Craftsman 1/2 hp chain drive, manufacture date: 11/93.  Model: HBW0777.  Logic Board Part No: 41A4315-7A.  If anyone has the owner's manual for one of these please forward the URL.