Battery backup indicator beeps or flashes; logic board LED flashes 5 times, pause, then 1 time (5-1) on Chamberlain battery backup models.

Safety first: Unplug the opener before servicing the battery. Batteries can leak corrosive electrolyte; wear eye protection and gloves.

Steps to fix:

• Locate battery compartment: On most Chamberlain units, the battery is in a compartment on the side or back of the opener head.
• Inspect connections: Open the cover and verify the red and black leads are firmly attached to the battery terminals. Clean any corrosion with a baking soda solution and a small brush.
• Check battery date: Most backup batteries last 3–5 years. If the date code is older, replace the battery with a Chamberlain-compatible 12V battery.
• Charge and test: After installing a new battery, plug the opener back in and allow several hours for charging. The beeping and 5-1 code should clear.