Garage Door Remote Battery: Which One It Takes and How to Change It

Question 01

What battery does a garage door remote take?

A garage door remote usually takes a lithium coin cell. According to B&D, its Tri-Tran+ Premium and TB6 remotes take a CR2032. Merlin says its remotes commonly take a CR2032 or a CR2025, depending on the model. A wall-mounted remote can be different: B&D's takes AAA alkaline batteries, not a coin cell.

For any other brand, check the manual for your remote model. If the manual is long gone, the battery itself tells you, which is the next question.

Question 02

How do I find the battery size for my remote?

Open the remote and read the code stamped on the face of the old battery, such as CR2032 or CR2025. B&D says to always use the exact type printed on your existing battery, because even a half-millimetre difference can change how it fits and works. The remote's manual lists it too.

The two common coin cells look almost the same. B&D gives the CR2032 as 3.2 mm thick and the CR2025 as 2.5 mm. B&D also says the CR2032 holds a little more charge, which tempts people to swap up. Don't. B&D warns that a CR2032 in a remote built for a CR2025 could end up damaging the contacts or the housing.

• Take the old battery with you to the shop, or photograph the code on it.
• Buy in child resistant packaging. The ACCC says to check that replacement button batteries come in child resistant packaging.
• Skip rechargeables. B&D says rechargeable batteries may not give the correct voltage and tend to lose charge faster.

Question 03

How do I change the battery in a garage door remote?

Open the case, note which way the old battery faces, swap in the same type and close it up. B&D says most of its remotes open with a small slot or screw on the back cover. Merlin says some of its remotes need a small screwdriver and others pull apart. Then press a button and check the door responds.

1. 01Pick your spot. The ACCC says to change button batteries on a flat surface and away from children, so a loose cell can't roll anywhere small hands reach.
2. 02Open the case. Look for a slot, a screw or a seam on the back. Merlin says to use a small screwdriver on models that need one. Lever gently so the plastic clips don't snap.
3. 03Find the battery. On Merlin remotes, Merlin says it usually sits behind the circuit board, so you may need to lift the board out carefully.
4. 04Note the way it faces. B&D says the positive (+) side usually faces outwards, but to confirm before you take it out. A quick photo saves guessing.
5. 05Fit the new battery. Use the exact type that came out and make sure it sits firmly under the contacts.
6. 06Close the case and test. Stand near the door and press the button. Check the case shuts fully all the way round.
7. 07Deal with the old battery straight away. Tape both sides and put it out of reach until it goes to recycling. The safety question below covers why.

Question 04

Do I need to re-code the remote after changing the battery?

Usually not. B&D's battery steps end with closing the case and testing the remote, and only then does B&D say that if the remote still doesn't work, try reprogramming it using your opener's manual. So test first. Re-code only if the remote stays dead with a fresh, correctly fitted battery.

If you do need to re-code, the steps depend on your opener's brand and model, and getting them wrong can wipe every remote at once. The remote not working guide explains how coding works and links each maker's own instructions for B&D, Merlin, Steel-Line and ATA openers.

Question 05

How can I tell my remote battery is going flat?

Watch the light on the remote and the distance it works from. Merlin's E970M instructions say that if the battery is low, the remote's LED will not flash when you press the button. A remote that only works when you're close, or needs several presses, also points to a tired battery, especially one over a year old.

• The light is dim or doesn't flash when you press a button.
• Range is shrinking. You have to be in the driveway, then right at the door.
• It takes two or three presses where one used to do it.
• A second remote works fine on the same door, which rules out the opener.
• The wall button still works, so the opener has power and the motor runs.

B&D adds that the wrong type or a poor-quality replacement can shorten battery life and weaken range, so a cheap battery from the back of a drawer can look like a fault. If the light flashes brightly and the remote still won't work from close range, the battery is probably not your problem.

Question 06

What makes a garage remote battery go flat faster?

Heavy use and heat are the main drains. B&D says lithium coin cells last 1 to 2 years in most cases, but heavy daily use can shorten that, and extreme heat or cold reduces their capacity. Merlin says the lithium battery in its E970M remote should produce power for up to 3 years.

B&D gives four ways to get more life from a battery:

• Store remotes away from direct sunlight or moisture.
• Avoid pressing buttons repeatedly or holding them down.
• Keep spare batteries in their original packaging until you need them.
• Fit a wall-mounted remote in high-use areas, so the handheld remotes do less work.

A remote that rattles around in a bag with keys can also get its button pressed by accident, which runs the battery down without you knowing. A clip on the car visor or a spot in the console is kinder to it.

Question 07

How do I handle a coin battery safely around kids?

Treat every coin battery, new or flat, as dangerous to a small child. The ACCC says a swallowed button battery can cause serious injury in as little as two hours, and the results can be fatal. The ACCC rates lithium cells, the type in most garage remotes, as the highest risk.

The ACCC gives two reasons. Lithium cells are usually larger, so they are more likely to get stuck in a child's throat, and their higher voltage can cause damage more quickly.

• Store new and used batteries out of sight and out of reach. The ACCC suggests lock boxes, secure cupboards or high spaces.
• Tape the old one straight away. The ACCC says to put sticky tape around both sides as soon as you've finished with a button battery.
• Don't trust a flat battery. Merlin's remote instructions say flat batteries can still be dangerous.
• Check the remote's case. A remote dropped on the driveway can crack. If the battery compartment won't close securely, Merlin says to stop using it and keep it away from children.
• Tell grandparents and carers where the remotes and spares live.

Australia has rules on this. The ACCC says there are 4 mandatory safety and information standards for button and coin batteries and the products that contain them, covering how batteries, products and packaging are designed and tested, and the warnings that must come with them.

Question 08

Is the remote battery the same as the opener's backup battery?

No. The remote's coin cell only powers the signal from your hand. A backup battery sits in the opener and keeps the motor running in a blackout. Merlin says its openers don't use a battery unless a backup system is installed, and that backup is typically a 12V rechargeable battery specific to the model.

This matters in a power cut. B&D says that in a power failure you can't open or close the door automatically unless battery backup is fitted to the opener. A fresh remote battery won't help when the opener itself has no power. B&D also says battery backup can be added to compatible openers, or you can choose an opener that has it built in.

If an opener with battery backup starts beeping, the opener beeping guide explains what each pattern means, and the motor replacement cost guide covers openers with battery backup.

Question 09

What if a new battery doesn't fix the remote?

Then the fault is somewhere else. B&D lists worn buttons, where the contact pads inside the remote wear out, signal interference from nearby devices or thick walls, and the opener's receiver, which might need servicing. Check lock mode, try a second remote and test the wall button before you assume the opener has failed.

The remote not working guide runs through those checks in order, from lock mode to the safety beams. If the wall button is dead as well, or a re-coded remote still won't work, the opener is the likely problem. That's where Thom comes in, with garage door repairs and garage door motor replacement across the Sunshine Coast from his base in Maroochydore.