You’ve clicked your fob button multiple times, but you still can’t get your car door open. After several attempts and pulling at your door handle, you finally get the door to unlock.
Now that you’re inside, you notice a ‘key fob battery low’ light on your dashboard which brings several questions to mind, like what it means, how to replace fob batteries, and how to start your car with a low fob battery.
Well, we’ve got you covered!
We’ll discuss all that and answer some other key fob-related questions.
This Article Contains
- What Does the “Key Fob Battery Low” Light Mean?
- What Are the Signs of a Low Key Fob Battery?
- How To Replace a Key Fob Battery
- How Do You Unlock Your Car With a Dead Fob Battery?
- How Do You Start a Car With a Low Battery Fob?
- 4 Other Key Fob FAQs
Let’s unlock the information.
What Does the “Key Fob Battery Low” Light Mean?
The dashboard warning light system helps update drivers on the status of their vehicles.
The ‘key fob battery low’ light on the dashboard represents a low battery warning message for your keyless remote battery. Ignoring this low battery indicator means you’ll start experiencing issues.
Worst case scenario:
If you disregard this low battery warning and the keyless remote battery dies, you could end up locked out of your car or even stranded.
However, the fob is not powered through your car battery but usually by a coin cell CR2032 battery inside, so it’s neither a costly nor difficult fix. All you need is a fresh battery, do the replacement, and your low battery message should go away.
Note: Different batteries may be used based on your car make and model.
To avoid the worst-case scenario, let’s see how you can tell your keyless remote battery is low.
What Are the Signs of a Low Key Fob Battery?
There are a few things that point to your key fob battery being low:
- The keyless remote isn’t very responsive
- Its range decreases, so you need to be closer for the unlock button to work
- Push button engines might not recognize the key and have difficulty starting
- The little LED light on the keyless remote is off or very weak
- Your car may have a warning light that points to a keyless remote battery low
Now that you’re certain about a low fob battery, let’s see how to replace it to avoid having a fob with a dead battery.
How To Replace a Key Fob Battery
Luckily, the battery replacement process is very straightforward.
Here’s how to do it:
1. Get the Right Battery Type
There should be an embossed number on the side of your car key indicating the battery type you need. Purchase a new battery as indicated on your car key fob.
2. Open the Fob Key
Locate the latch, switch, or screw at the back of the car key fob and open it using your fingernails or a small flathead screwdriver. Pull apart the two halves once your fob’s battery cover is open.
3. Remove the Old Battery
Pay attention to how the old battery is installed. Some fobs may have clips over the battery — use a screwdriver to lift them. The circuit board may be exposed during this process. Be careful not to damage the circuit board, or you might end up needing a new fob.
4. Do a Battery Replacement
Place the new battery inside the fob like you removed the old one. Make sure you’re using good batteries for replacement.
5. Close Up the Fob and Test the Fob Button
Once you have a fresh battery in the fob, test to see if everything works fine. If your fob button isn’t working, try to reset the programming instructions. Here’s a summary of the reset programming instructions:
- Put your key into the ignition switch and turn, or activate your ignition button to activate your dashboard lights — the low battery indicator should have disappeared.
- Turn the key to the lock position.
- Repeat the steps until you hear a chiming or reset sound.
- Then press the unlock button and lock button on the fob.
If, after all that, the fob still doesn’t work, then you may need a new fob.
Now, if you don’t have access to good batteries and need to open your car immediately (and you don’t have a second fob), here’s what to do.
How Do You Unlock Your Car With a Dead Fob Battery?
Car manufacturers considered the dead battery issue when designing the fob. They’ve installed a backup mechanical key (a physical key) inside the fob, so you don’t have to visit a service center.
Here’s how to access the mechanical key:
- Locate and press the small release switch behind your fob.
- Remove the battery cover.
- Open the fob to access the spare metal key — and voila, you can now open your car!
You can also refer to your owner’s manual to check where to find the physical key.
Additionally, some manufacturers have a remote unlock app you can use to get into your car with a dead remote battery:
- Ford: You can access your car using the SYNC Connect or FordPass feature
- Honda: Honda Motor Company vehicle owners can access the HondaLink app
Now that you’ve gotten in your car, wondering how to start your vehicle with a low fob battery? Let’s discuss.
How Do You Start a Car With a Low Battery Fob?
Vehicles with the standard insert key ignition can use the spare metal key. But key battery low situations are different for push start button vehicles. They rely on a signal from the smart key to activate your ignition.
Try holding the low battery fob key directly against the start button so it can detect the signal. Some push-start vehicles might even have a slot on the dash, steering column, or console where you can insert the fob key to start your car. Check your owner’s manual to find out.
Are there other key fob questions rattling around in your brain?
Let’s get to them.
4 Other Key Fob FAQs
Here are the answers to some frequently asked questions about key fobs:
1. What Type of Batteries Do Fobs Need?
Key fobs usually use a 3V button cell (coin cell) CR2032 battery. Your fob might also use CR2016, CR1616, CR2025, and CR2450.
2. How Much Does Replacing Fob Batteries Cost?
This is an easy DIY job, so you’ll only have to buy the replacement battery for your remote key fob. The replacement battery can cost approximately $6-7, depending on the brand and amount of batteries you buy.
For example, an Energizer original battery pack of two costs around $6, while a Panasonic original battery pack of four costs $7. You can easily purchase the battery packs at Walmart — no need to go to a service center.
3. How Long Do Key Fob Batteries Last?
The battery life depends on whether you’ve got a regular remote key fob or a smart key.
A smart key fob battery can last up to 2 to 3 years. A regular fob battery can last around 4 to 6 years. There are signs pointing to a low fob battery you should notice.
4. What’s the Difference Between a Smart Key and a Key Fob?
A key fob has respective buttons to lock or unlock your vehicle or to open your boot. A smart key fob uses radio pulses to lock and unlock your vehicle, allowing keyless entry. Sensors on your vehicle pick up the signal when the car key is close enough and activate keyless entry.
Modern push-start vehicles also use this technology to start the ignition, allowing for a button start. Your car must register the smart key in proximity for the remote start to work.
Keep Moving with AutoNation Mobile Service
Something as simple as a low fob battery can cause a lot of inconvenience, especially if you don’t have a second fob as backup. Your dashboard lights, like the key fob low battery light, can help you deal with minor issues before they become a big problem.
Need some help diagnosing various dashboard lights?
Call AutoNation Mobile Service today.
Our qualified mobile mechanics will come straight to your driveway and fix any car issues you’re facing. Whether it’s a car key replacement or fixing a car door problem, all AutoNation Mobile Service repairs come with a 12,000-mile/12-month warranty.
Use our convenient online booking services to schedule a mechanic visit easily.