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How do I replace an Ac Motor in a Garage Door Opener?

One of the eyes on the safety sensor emits a beam of light and the other receives it. The closing door can be reversed if an object, person or animal blocks the beam. The sensor eyes should be connected to short wires at the motor unit. Click the remote while holding the sensors close together. The safety sensors should be replaced if the door doesn't close and the lights don't blink.

Speed signals are sent to the logic board from the RPM sensor. When the logic board doesn't receive speed signals from the RPM sensor, it shuts off the motor and flashes a learn light five times. When the logic board is not receiving speed signals, the door only moves 6 to 8 inches. If the door only moves a short distance, the learn light should be replaced.

The chain and cable assembly are driven by the motor unit's sprocket. The trolley lifts and lowers the garage door. Don't replace the chain if it's damaged.

The chain is raised and lowered by the AC motor that drives the gears. The garage door opener's motor should be replaced if it doesn't run.

The garage door opener is fastened to the garage door with brackets. The brackets can wear out. If the components need to be replaced, inspect the brackets and other door hardware.

Follow these steps to fix your issue:

  1. Disconnect power

    The power cord and motor unit of the garage door opener can be accessed using a step ladder. The garage door opener needs to be unplugged.

  2. Take the garage door opener down

    To hold the garage door opener during the repair, place a work table under the motor unit. The trolley needs to be released from the garage door. If the garage door isn't already closed, shut it. The straight door arm has a ring on it. The garage door can be disconnected from the outer trolley by pulling out the clevis pin. Place the straight and curved arms against the garage door. If necessary, use a helpers. The wall control and safety sensor wires are connected to the motor unit. The wall control and safety sensor wires are connected to the motor unit. You will refer to the photo when you connect the wires. The wall control and safety sensor wires need to be disconnected. The light cover needs to be closed. The motor unit is secured with nuts, bolts, and lock washers. Attach the motor unit to the ceiling with one hand. Carefully lower the motor unit and secure it on the step ladder. Take the motor unit out of the stepladder and put it on the table. You need to move your stepladder by the garage door to get rid of the rail. The clevis pin has a ring on it. Pull the clevis pin out of the rail with one hand. If you want the rail to be level with the motor unit on your table, lower it and rest it on a rung of the stepladder. If you want to avoid scratching a decorative garage door, remove the nuts, bolts and washers from the curved arm and rest it against the door when you disengage the garage door from the outer trolley. When taking the garage door opener down, you may want to have a helpers help you.

  3. Remove the RPM sensor

    Light bulbs and light covers need to be removed from the motor unit. Remove the screws from the motor unit cover and flip the unit over. Plug the sensor wire harness back in. The motor shaft has an interrupter cup. The mounting clip has a RPM sensor on it. The wiring connections for the wall control and safety sensors are not on the left side motor unit cover.

  4. Install the new RPM sensor

    The mounting clip should be pushed into the RPM sensor. The new sensor can be connected to the RPM sensor wire harness. The motor shaft has an interrupter cup on it. Remove the motor unit cover and secure it with the screws. Light bulbs and light covers need to be reinstalled.

  5. Reinstall the garage door opener

    The rail end should be connected to the brackets using a clevis pin and ring. Set the motor unit on top of the step ladder when you position the ladder under the ceiling. Use nuts, bolts and lock washers to put the motor unit back in the ceiling. The wall control and safety sensor terminals can be accessed by opening the light cover. Attach the wall control and safety sensor wires to the motor unit using your photo as reference. The light cover must be closed. Attach the straight door arm to the outer trolley by using the clevis pin and ring. The trolley must be re-engaged. If you disconnected the curved door arm from the straight door arm while freeing the garage door from the outer trolley, you should use the bolts, lock washers and nut.

  6. Reconnect electrical power

    The garage door opener should be plugged in.

  7. Disconnect the power

    The power cord and motor unit of the garage door opener can be accessed using a step ladder. The garage door opener needs to be unplugged.

  8. Remove the sensors

    The safety sensor has a wing nut on it. The sensor needs to be removed from the brackets. Leave enough slack in the control wire to connect the new sensor after cutting the wires about an inch from the safety sensor. The process should be repeated for the other safety sensor.

  9. Connect the new safety sensor wires

    The control wires need to be separated from the new sensor. Use the crimp wire nut to connect the black-striped control wire to the black-striped safety sensor wire. The wires are connected the same way. The process should be repeated for the other safety sensor. If you're not using the crimp wire nuts that come with the new safety sensors, you can connect the wires using wire nuts.

  10. Install the new safety sensors

    The wire nut is needed to secure the safety sensor. The process should be repeated for the other safety sensor.

  11. Reconnect electrical power

    The garage door opener should be plugged in.

  12. Line up the safety sensors

    The receiving sensor should have a green indicator light.

  13. Test the safety sensor

    You can open the garage door. To block the beam, place a box between the safety sensors. The garage door could be closed using a remote. The door should remain open and the lights should blink. The logic board should be replaced if the garage door opener closes the door.

Time required:

60 minutes.

You would need the following tools:

needle nose pliers, nut driver set, pliers, safety glasses, socket wrench set, step ladder, work gloves, work table.

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