Five Signs That Your Car Key Battery is Dying

Car key fob batteries don’t last forever, and when they fail it can create frustrating malfunctions that are often easy to fix. Learn the five primary signs that your key fob battery is dying.

Open your key fob at the seam (use your finger or a screwdriver) and pop out the old battery. Replace it with a new one of the same type, taking care to insert it correctly.

How to Replace a Key Fob Battery

While key fobs use a wireless signal to communicate with your car’s computer, they still need power to operate. The most common reason that your key fob won’t turn on is because of a dead battery. Fortunately, replacing the battery is an easy process that you can do yourself.

Start by locating the battery compartment. It is usually found on the backside of the fob. There may be a slot, notch, or sliding cover that you need to push in order to remove the cover and expose the battery. Once you find it, use a screwdriver or coin to gently pry open the battery compartment. Try not to use too much force, as this could damage the circuit board and antennas.

Once the cover is off, remove the old battery and replace it with a new one. Take a photo or make a note of the orientation of the battery before removing it in order to ensure that you put the new battery in correctly. Once the new battery is inserted, snap the fob’s halves back together and test it.

While most key fobs use a standard watch bmw battery battery (CR2032), it is important to research the type of battery required for your specific model and year car. Some battery types that you might see in an auto parts store include CR2025, CR1616, and CR2016.

Honda Key Fob Battery Replacement

Car key fobs make driving easier by giving you the ability to unlock the doors and start your engine remotely. These convenient features operate on a small battery that doesn’t last forever. When it dies, the key fob may show telltale signs like requiring you to get closer and closer before it will work, or not working at all.

You can replace the Honda key fob battery at home if you know which type of battery to buy. Most key fobs use standard watch batteries, CR2025 or CR2032, but some models require a different format. Check the owner’s manual or look on the old battery to find out which type you need.

To open the key fob case, wedge a flathead screwdriver between the case’s fasteners to pry it apart. Some cases have a notch to help you with this. Once you’ve opened the case, carefully remove the battery. Take note of the positive (+) and negative (-) sides so you can install the new battery correctly.

Once you have the new battery, line up the back half with the front and press them together until you hear a snap. Be careful not to over-press or you may damage the circuit board inside. Now your Honda key fob is ready to go for more Irvine commutes with the convenience of remote access.

Toyota Key Fob Battery Replacement

Your Toyota key fob provides the convenience of keyless entry and remote start, but it also requires a small battery to function. If yours becomes sluggish or stops working altogether, that indicates that the battery is dead and needs replacing. The good news is that changing a car key fob battery can be done easily at home, saving you money and time on a dealer visit.

Most Toyota fobs open in a clamshell design, with a seam that divides the front and back of the device. To open them, you’ll need to remove the metal car key, which usually has a release tab or slot, then pry off a small panel on the backside of the fob that exposes the battery compartment. A screwdriver or another small, flat object will provide the leverage you need to pry this panel off. You’ll also want to keep track of any screws or clips that might fall out during this step, so you can put them back in place later.

Once you’ve opened your key fob case, gently lift up the circuit board and note the battery type. This should be written on the case or displayed somewhere on the board itself, and it will help you purchase the right replacement in the future. Most Toyota models use CR2032 batteries, which are available at many local stores or online and cost less than $5. Once you have the new battery, reinstall it and snap the fob case shut.

Nissan Key Fob Battery Replacement

Unlike some other brands, Nissan key fobs do not require you to reprogram the fob after changing its battery. Instead, you need to make sure the replacement battery is the right type for your model and that it has been installed properly. You may need to consult the owner manual to find specific instructions, but if you are handy with a screwdriver you can usually follow a general procedure.

Using a flathead screwdriver or a small coin, you can pry open the key fob along a seam that separates it into front and back halves. Be careful not to damage the plastic. Once you have the two halves separated, you can remove the old battery by inserting a screwdriver into the notch and gently pulling up on one edge. Generally, the dead battery will pop out and you can then insert the new battery. Make sure it is in the correct orientation, with the positive “+” side facing up. Finally, you can reassemble the key fob and reinsert the metal key.

Once you replace the battery, test its functions by pressing the lock and unlock buttons several times while car battery retailers standing next to your Nissan. If the keys still don’t work, you may need to call a mechanic or your local Nissan dealership for help. They can diagnose whether the problem is with your fob’s internal programming or a bad battery.