Need a manual for Liftmaster Model 1156LM garage door opener

SOURCE: Sears Craftsman Garage Door Opener Wireless Keypad Model and a LiftMaster Chamberlain Professional Garage Door

Hello,

I had the same frustrating dilemma with my Craftsman LiftMaster garage door and Keypad, Model 139.53754-01 (dated 10/06; and has the # 315 MHz).

To resolve “the dilemma”, grab your keypad, climb up on a ladder to access the garage door opener’s motor unit. On the right side of the motor unit, remove the white plastic casing by pressing buttons on each side and pulling down. This will expose the programming area, and for our purposes, the “Learn” button.

1. On the motor unit, press and release the “Learn” button. The Learn indicator light will glow steadily for 30 seconds.

2. Within 30 seconds, enter a four digit personal identification number (PIN) of your choice on the keypad. Then press and hold the ENTER button.

3. Release the ENTER button when the motor unit lights blink. The code has been “learned”/stored/activated.

Good Luck, and I Hope this Helps!
Gail
For possible future reference:

How to change an existing, known PIN
(Changing an existing PIN can be done with the wireless remote keypad, and does not require access of the motor unit.)

From the keypad:

1. Enter the four digits of the present PIN, then press and hold the # button. The opener light will blink twice. Release the # button.

2. Enter your new 4-digit PIN and press Enter. The motor unit lights will blink once when the PIN has been “learned”/stored/activated. Test by entering the new PIN, and pressing Enter.

SOURCE: Replacement for Garage Door Remote

The red button is the "learn" button. No resets.

SOURCE: Liftmaster wireless keypad closes but won't open the door

If you are sure the battery is good you have a bad keypad. The signal strength is so weak it will not penetrate the door.

SOURCE: I NEED TO PROGRAM MY LIFTMASTER GARAGE DOOR

If you have the correct remotes for your opener you can program them like this:

Locate the smart/learn button on the back of the motor unit. Press and hold the button on your remote while you press and immediately release the smart/learn button. Do this for each remote.

SOURCE: Programming remote, unit will not flash.

The easiest way to program is to hold the button on the remote while you press and immediately release the smart/learn button. If it worked before there is no reason for it not to work now unless it totally failed.