The modern push to start ignition system has become a staple in vehicles, offering convenience and a touch of technological sophistication. But what happens when the key fob battery dies? Can you still start your car? The answer is usually yes, and this article will delve into the various methods and reasons behind it.
Understanding the Push to Start System
The push to start system, also known as keyless ignition, relies on radio-frequency identification (RFID) technology. Your key fob emits a low-frequency signal that the car’s computer system recognizes. When the system detects the correct signal, it allows you to start the engine by pressing the start button. This eliminates the need for a traditional key. However, this reliance on technology can also raise concerns about potential failures, especially when the key fob’s battery runs out.
The Role of the Key Fob Battery
The key fob battery is essential for transmitting the signal that allows the car to authenticate the key. Without a functioning battery, the fob cannot communicate wirelessly with the vehicle. The type of battery varies depending on the car model, but they are generally small, coin-shaped lithium batteries. Over time, these batteries naturally lose their charge, which can leave you stranded if you aren’t prepared.
Starting Your Car with a Dead Key Fob: The Backup Methods
Automakers anticipate the possibility of a dead key fob battery and have incorporated backup systems to ensure you can still start your vehicle. The specific method may vary depending on the make and model of your car, so consulting your owner’s manual is always the best first step.
The Physical Key Method
Many push to start vehicles also include a physical key hidden within the key fob itself. This key can be used to unlock the car door manually. Look closely at your key fob; there’s usually a small button or release that allows you to slide out the physical key.
Once you’ve unlocked the door, you may be wondering how this key will start the engine without an ignition cylinder. In some cases, the physical key can also be used to trigger the push to start system. Insert the key into a designated slot, which may be located in the glove compartment, under the steering column, or inside the center console. This insertion allows the car to recognize the key and enable the push to start button.
The Key Fob Proximity Method
Even if the key fob’s battery is completely dead, many vehicles can still detect the fob’s presence using near-field communication (NFC) technology. This method involves holding the key fob very close to a specific location in the car, usually the start button itself.
To use this method, press the start button with the key fob itself. The car’s sensors are designed to detect the RFID chip even with a weak or dead battery, as long as the fob is in very close proximity. The precise location may vary, so consult your owner’s manual for the exact placement.
Using the Car’s App (If Applicable)
Some newer vehicles come with a smartphone app that allows you to remotely start and control certain functions of the car. If your car has this feature and you’ve already set it up, you may be able to start the car using the app, even with a dead key fob. However, this method relies on a working smartphone and an active connection to the car’s telematics system.
Troubleshooting Starting Issues
If you’ve tried the backup methods and your car still won’t start, there might be other underlying issues.
Checking the Car Battery
A dead car battery is a common reason why a car won’t start, regardless of whether you have a push to start system or a traditional key. If the car’s battery is weak or dead, it won’t be able to power the starter motor, even if the key fob is working correctly.
You can try jump-starting the car with jumper cables and another vehicle. If the car starts after jump-starting, it indicates that the car battery is the problem. In this case, you should either replace the battery or have it professionally tested.
Inspecting the Starter Motor
The starter motor is responsible for cranking the engine and initiating the combustion process. If the starter motor is faulty, it may not be able to start the engine, even with a good battery and a working key fob.
Signs of a failing starter motor include a clicking sound when you try to start the car, a grinding noise, or the engine failing to crank at all. If you suspect a starter motor problem, it’s best to have your car inspected by a qualified mechanic.
Addressing Security System Issues
In some cases, the car’s security system may be preventing the engine from starting. This could be due to a malfunctioning sensor, a faulty immobilizer, or a problem with the car’s computer system.
If you suspect a security system issue, try resetting the system by disconnecting the car battery for a few minutes and then reconnecting it. If that doesn’t work, you may need to have the car diagnosed by a professional who can access the car’s diagnostic system.
Preventive Measures: Avoiding Key Fob Battery Issues
Taking proactive steps can minimize the chances of being stranded with a dead key fob battery.
Regular Battery Replacement
Replace your key fob battery proactively every one to two years. This will prevent the inconvenience of finding yourself with a dead battery at an inopportune time. The specific battery type required will be listed in your owner’s manual or can be determined by removing the battery cover on your key fob and inspecting the old battery.
Keeping a Spare Battery
Always keep a spare key fob battery in your glove compartment or wallet. This simple precaution can save you a lot of trouble if your key fob battery dies unexpectedly. Make sure to store the battery in a safe place where it won’t be damaged or discharged.
Monitoring Battery Warnings
Pay attention to any warning messages or indicators on your car’s dashboard related to the key fob battery. Some cars display a “low key fob battery” warning when the battery is getting weak. Heeding these warnings and replacing the battery promptly can prevent a complete failure.
Key Fob Battery Replacement: A Step-by-Step Guide
Replacing your key fob battery is a relatively simple task that you can usually do yourself. However, it’s important to follow the correct procedure to avoid damaging the key fob.
Gathering the Necessary Tools and Materials
Before you begin, gather the necessary tools and materials. You’ll need a small flathead screwdriver or a similar tool to pry open the key fob, a new key fob battery of the correct type, and a clean, well-lit workspace.
Opening the Key Fob Casing
Locate the small notch or opening on the key fob casing. Insert the flathead screwdriver into the notch and gently twist to pry open the casing. Be careful not to apply too much force, as this could damage the plastic.
Removing the Old Battery
Once the key fob is open, carefully remove the old battery. Note the battery’s orientation (positive and negative sides) so you can install the new battery correctly. You may need to use the screwdriver to gently pry the battery out of its compartment.
Inserting the New Battery
Insert the new battery into the compartment, making sure to match the correct orientation. The positive (+) side of the battery should usually face up. Press the battery firmly into place.
Closing the Key Fob Casing
Align the two halves of the key fob casing and press them together until they snap securely into place. Ensure that the casing is completely closed and that there are no gaps or loose parts.
Testing the Key Fob
After replacing the battery, test the key fob to make sure it’s working correctly. Try unlocking and locking the car doors remotely, and attempt to start the engine using the push to start button. If the key fob doesn’t work, double-check that the battery is installed correctly and that the casing is properly closed.
Advanced Key Fob Issues and Solutions
While a dead battery is the most common key fob problem, other issues can arise.
Key Fob Reprogramming
Sometimes, the key fob may need to be reprogrammed to communicate with the car’s computer system. This can happen if the key fob has been damaged, if the car’s battery has been disconnected for an extended period, or if the car’s computer system has been updated. The reprogramming process varies depending on the car make and model, and it may require special equipment or software. Some dealerships offer key fob reprogramming services, or you may be able to find a locksmith who specializes in automotive key programming.
Key Fob Damage and Repair
If your key fob has been dropped, exposed to water, or otherwise damaged, it may not function properly. In some cases, the damage can be repaired, such as replacing a broken button or resoldering a loose connection. However, in other cases, the key fob may need to be replaced entirely.
Key Fob Replacement
If your key fob is lost or irreparably damaged, you’ll need to obtain a replacement. The process for obtaining a replacement key fob varies depending on the car make and model. You can typically purchase a replacement key fob from the dealership or from a specialized locksmith. Be prepared to provide proof of ownership and identification. The replacement key fob will need to be programmed to work with your car’s security system.
The Future of Keyless Entry
The technology behind keyless entry and push to start systems continues to evolve. We are already seeing advancements like smartphone-as-a-key technology becoming more prevalent, which further reduces reliance on physical key fobs. Biometric authentication may also play a larger role in the future, adding an extra layer of security and convenience. As these technologies advance, they will likely become more reliable and user-friendly, further streamlining the car ownership experience.
What happens if my key fob battery dies while I’m away from home?
Most push-to-start vehicles have a backup plan for a dead key fob battery. This usually involves a hidden physical key blade within the fob itself. You can use this key to manually unlock the driver’s side door. Consult your owner’s manual to locate the keyhole, as it’s often concealed behind a plastic cover on the door handle.
Once inside, you’ll need to use the emergency start procedure. This usually involves holding the fob directly against the steering column (often marked with a key symbol) or placing it in a designated slot or cup holder. This allows the car to detect the fob’s low-power signal and start the engine. The exact procedure varies by manufacturer and model, so always refer to your owner’s manual for specific instructions.
How can I unlock my car if my key fob is dead and there’s no physical key?
In the rare case where your key fob is dead and lacks a physical key, or you’ve lost it, your options are more limited. Contacting roadside assistance is often the quickest solution. They may use specialized tools to unlock your car without causing damage.
Alternatively, consider contacting your car dealership. They can usually verify your ownership and use the vehicle identification number (VIN) to generate a replacement key or provide a temporary unlocking solution. However, this process may take longer and be more expensive than roadside assistance.
Where is the emergency key slot usually located in a push-to-start car?
The emergency key slot, or the location where you need to hold the key fob against the car to start it with a dead battery, varies depending on the make and model of your vehicle. Common locations include the steering column, often marked with a key or fob symbol.
Another potential location is the center console, either in a cup holder or a specifically designed slot. Some vehicles might even require you to place the fob under the start button itself. Always consult your owner’s manual; it provides the exact location and instructions for your specific vehicle.
Can cold weather drain my key fob battery faster?
Yes, cold weather can significantly impact the performance of key fob batteries. Batteries rely on chemical reactions to produce power, and these reactions slow down in cold temperatures. This can reduce the battery’s voltage and overall lifespan, making it seem like the battery has died prematurely.
This effect is temporary, and the battery’s performance may improve when it warms up. However, repeated exposure to cold temperatures can permanently damage the battery and shorten its lifespan. Consider keeping your key fob in a warmer location during extremely cold weather to help preserve the battery.
How often should I replace my key fob battery?
The lifespan of a key fob battery depends on several factors, including usage frequency, environmental conditions, and the battery’s quality. A typical key fob battery lasts between one to three years. However, it’s wise to proactively replace it every two years as a preventative measure.
Watch for warning signs of a weakening battery, such as reduced range, inconsistent locking/unlocking, or a warning message on your car’s dashboard. Replacing the battery before it completely dies can prevent the inconvenience of being stranded with a non-functional key fob.
What type of battery does my key fob use?
The type of battery your key fob uses varies depending on the make and model of your car. Common battery types include CR2032, CR2025, and CR2450. These are coin-cell batteries, and the numbers indicate their size and voltage.
The easiest way to determine the correct battery is to check your owner’s manual. Alternatively, you can open the key fob and visually inspect the battery that’s currently installed. Make sure to purchase the exact same type of battery to ensure proper functionality.
Is it possible to start a push-to-start car with a completely dead car battery, even with a working key fob?
No, a push-to-start car cannot be started with a completely dead car battery, even if the key fob is working perfectly. The key fob transmits a signal to the car’s computer, but the computer and the starter motor require power from the car’s battery to function. A dead car battery means there’s no power to initiate the starting sequence.
In this scenario, the issue isn’t with the key fob, but with the car’s battery itself. You’ll need to jump-start the car using jumper cables and another vehicle with a charged battery, or replace the dead car battery altogether. Once the car’s battery is sufficiently charged, the push-to-start system will function normally with a working key fob.