Garage Backup Battery in Plano, TX

A liftmaster battery is shown on a white background.

Does it need to be replaced?

Having a backup battery in your opener can be a huge lifesaver. If your power ever goes out or the power source to your opener stops functioning, the backup battery will activate allowing the opener to still function properly. If the backup battery is dead, this feature is useless. How can you tell if your battery is dead or going to die? Once the battery begins to die the opener unit will begin to beep, notifying you of the problem. Be sure to check that the beeping isn’t coming from a smoke detector or other electronic device. Once you have narrowed down the location of the beeping you are ready to replace your battery.


Where is the backup battery?

The location of the backup battery varies depending on the opener. The Liftmaster 8550 belt driven opener, for example, uses a 485LM backup battery located behind the light cover. Older models, the Jackshaft 8500, and heavy duty openers use the 475LM standby power system. The 475LM may be mounted either directly on top of the motor unit or secured on a structural support above it.

A man is standing on a ladder fixing a garage door opener.

Replacing the 485LM backup battery


When replacing the 485LM, disconnect the opener from the power source. Once the opener is unplugged, remove the light cover by gently pulling it away from the opener. With the light cover removed, unscrew the lightbulb giving you full access to the battery. Now, using a Philips head screwdriver, remove the plastic cover exposing the battery. Remove the old battery and discard (or we can discard of it for you). Partially insert the new battery into the motor unit with the terminals facing out. From this point, connect the red (+) and black (-) wires from the opener to the corresponding terminals on the battery. After completing those steps, replace the battery cover, lightbulb, and light cover.


Replacing the 475LM standby power system


Directly to the motor unit:


Position the 475LM directly on top of the opener with the power cord drawn out from beneath the battery, sitting firmly on top of the opener. Be sure to adjust the placement of the angle iron (the support system for the opener) so that it is out of the way of the battery installation. Align the two screws


Secured to a structural support:


The 475LM can be mounted to either the ceiling or a wall within 3’ of the opener motor. Secure the battery in the desired position using the mounting holes on either side and the 1-1/2” lag screws provided.


Connecting the battery to the motor unit:


Before connecting your battery to the opener, be sure to unplug it from the power source. Connect the 475LM power cord to the end panel of the motor. Once the battery is connected to the opener, plug the opener back into the power source. This will allow the battery to activate causing all LED’s to turn on for 3 seconds. The green LED will flash notifying that the battery is installed properly and beginning to charge. Allow 24-48 for the battery to fully charge.


Need a backup battery?

Stop by our conveniently located showroom to replace your dead backup battery. Don’t want to do it yourself? Call our office at 972-422-1695 to schedule a time for one of our trained technicians to come out and install it for you!


By  Nick McGregor , General Manager of  Plano Overhead Garage Door



Tags:  Garage Opener Backup Battery How to Replace Your Backup Battery in Plano, TX How to Replace Your Opener’s Backup Battery in Plano, TX Internal Backup Battery Garage Door Opener Liftmaster 485LM Your Place for Garage Door Service in Plano, TX


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