Experiencing issues with your 2009 Nissan Altima key fob after a battery replacement can be frustrating. Many owners find themselves locked out or unable to start their vehicle despite installing a fresh battery. Fortunately, these problems are often resolvable with simple DIY procedures, saving you a trip to the dealership. This guide will walk you through common key fob issues after battery replacement and provide effective solutions to get you back on the road.
Issue #1: “Invalid Key ID” or “No Key Detected” Messages
One frequent problem after replacing the battery in your 2009 Nissan Altima key fob is encountering “Invalid Key ID” or “No Key Detected” messages on your dashboard. Alongside this, the door request buttons on your vehicle might stop functioning. However, the remote buttons on your key fob for locking, unlocking, and the trunk release typically continue to work, and you can usually start the car by pressing the start button directly with the key fob or using the emergency key slot if your model has one.
Solution: Re-syncing your key fob after battery replacement is often straightforward. Follow these steps to resolve the “Invalid Key ID” or “No Key Detected” issue:
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Remove the Backup Key: Take out the mechanical backup key from your 2009 Nissan Altima key fob.
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Enter the Vehicle: Get into your Nissan Altima, ensuring you have the key fob with you inside the car.
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Cycle Ignition (Without Brake): Press the start button twice without pressing the brake pedal. This will cycle the ignition to the “ON” position without starting the engine.
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Exit and Lock with Manual Key: Get out of your car, taking only the backup door key with you, and leave the key fob inside the vehicle. Close the driver’s side door.
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Lock and Unlock Manually: Insert the backup door key into the driver’s side door lock. Turn the key to the left to lock the door. You will hear the locking mechanism engage. Then, turn the key to the right to unlock the door, and you’ll hear the unlocking mechanism again.
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Re-enter and Turn Off: Re-enter your Nissan Altima, leaving the key fob inside. Press the start button one more time (without pressing the brake) to turn the ignition to the “OFF” mode.
After completing these steps, the “Invalid key ID” messages should disappear, and your 2009 Nissan Altima key fob should function normally again.
Issue #2: Key Fob Buttons Not Working (Remote Lock, Trunk, Panic)
In contrast to the first issue, you might find that everything works fine after a 2009 Nissan Altima key fob battery replacement except for the remote button functions. This means the buttons for remote door lock, panic alarm, remote trunk release, and remote start (if equipped) become unresponsive. The car starts and recognizes the key, but the remote features are dead.
Solution: This issue typically indicates that the ECU (Engine Control Unit), essentially your car’s main computer, needs a reboot to recognize the key fob’s button functions after the battery change. A “cold boot” of the ECU, with the key fob inside the car, will often reprogram the push-button functionalities. The easiest way to perform a cold boot is to disconnect the car’s main battery:
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Locate Car Battery: Open your Nissan Altima’s hood and locate the main car battery.
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Disconnect Battery: Using a wrench, disconnect the negative terminal of the battery. Wait for a minute or two.
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Reconnect Battery: Reconnect the negative battery terminal securely.
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Test Key Fob: Ensure your 2009 Nissan Altima key fob is inside the car and test the remote button functions. They should now be working correctly.
Keep in mind that disconnecting the car battery might reset the ECU’s learned settings. Your car may idle slightly differently for the first few miles after reconnecting the battery, but it will quickly return to its normal operating state.
Key Fob Battery and Preventative Maintenance
Replacing the battery in your 2009 Nissan Altima key fob before you encounter intermittent problems is a good preventative measure. This can help avoid memory corruption in the key fob caused by very low battery voltage. The correct replacement battery is a CR2032 button cell battery. While a CR2025 battery will also fit and function in an emergency, it is slightly thinner and has a lower capacity, meaning it won’t last as long as a CR2032.
Important Note: For either of the issues described above, it’s reported that reprogramming both key fobs simultaneously can be achieved by leaving both key fobs inside the car while performing the respective procedure. While this hasn’t been personally verified for multiple key fobs at once, it’s a potentially time-saving tip if you have two key fobs for your 2009 Nissan Altima experiencing issues.
By following these troubleshooting steps, you can often resolve common 2009 Nissan Altima key fob problems after battery replacement and regain full functionality of your keyless entry system.
