Smart car keys, or key fobs, offer convenience, but issues can arise, especially after battery replacement. A common question is: Will A Smart Car Key Work If Not Programmed? For Nissan owners, encountering problems like “Invalid Key ID” or non-functioning remote buttons after a battery change is not uncommon. Fortunately, in many cases, your Nissan smart key may not require full reprogramming. Here’s a guide to troubleshoot and potentially resolve these issues yourself.
Issue #1: “Invalid Key ID” or “No Key Detected” After Battery Replacement
One frequent problem with Nissan key fobs is receiving “Invalid Key ID” or “No Key Detected” messages after you’ve replaced the battery. You might also find that the door request buttons stop working. Interestingly, the key fob buttons for remote door opening might still function, and you can usually start the car by pressing the start button with the key fob itself.
Solution: A simple re-synchronization procedure can often fix this. Follow these steps:
- Remove the backup door key from your Nissan key fob.
- Enter your Nissan and ensure the key fob is inside the vehicle.
- Press the start button twice without pressing the brake pedal (this cycles from OFF to ACC to ON).
- Exit the car, leaving the key fob inside, and take the backup door key with you.
- Close the driver’s side door and insert the backup door key into the door lock.
- Turn the key to the left to lock the door. You should hear the locking mechanism engage.
- Turn the key to the right to unlock the door. Again, listen for the unlocking mechanism.
- Remove the door key and re-enter your Nissan.
- Press the start button one more time (again, without the brake) to turn the ignition to the OFF mode.
After this procedure, the “Invalid Key ID” messages should disappear, and your key fob should function normally.
Issue #2: Remote Key Fob Buttons Not Working After Battery Replacement
In contrast to the first issue, you might experience a situation where everything works fine except for the push-button functions on your Nissan key fob. This means the remote door lock, panic button, remote trunk release, and remote start (if equipped) are unresponsive.
Solution: This problem often indicates that the key fob’s push-button functions need to be re-programmed to the car’s ECU (Engine Control Unit). A “cold boot” of the ECU with the key fob inside the car can usually resolve this.
- The easiest way to perform a cold boot is to disconnect the main car battery under the hood.
- Wait for a minute or two.
- Reconnect the main battery.
When the ECU reboots, it will typically re-program the push-button functions of the key fob if the key is inside the vehicle. Keep in mind that disconnecting the battery may reset the ECU’s learned settings, potentially causing a slightly different idle for the first few miles of driving. This is normal and will correct itself quickly.
Preventing Key Fob Issues
Replacing your Nissan key fob battery before you encounter intermittent problems can often prevent these issues altogether. However, if the battery voltage gets very low, the key fob’s internal memory can become corrupted, and simply replacing the battery may not restore proper operation, necessitating the procedures described above.
It’s also worth noting that you can attempt to re-program multiple key fobs simultaneously by leaving them all inside the car when performing either of the solutions outlined.
Footnote: The correct replacement battery for most Nissan key fobs is a CR2032 button cell. A CR2025 can be used as a temporary substitute, but it is slightly thinner and has a lower capacity, resulting in a shorter lifespan.
