Why has my keyless entry stopped working?
Most issues stem from a dying key fob battery, a dead vehicle battery, or a need to re-sync the fob with the car. In many cases, replacing the battery or trying a spare resolves the problem without a trip to the shop.
Common causes
The following are the most frequent culprits behind a non-responsive keyless-entry system, ranging from simple battery issues to broader electrical faults within the vehicle.
Fob battery and related electronics
- Dead or weak battery in the key fob
- Fob needs re-programming or re-sync after battery replacement
- Intermittent transmission due to damaged fob or corrosion in button contacts
Conclusion: A failing fob battery or a required re-sync covers many outages and is usually the quickest fix.
Vehicle electrical issues
- Weak or dead car battery, or a failing alternator
- Blown fuse affecting the central locking system
- Malfunctioning receiver or control module inside the car
Conclusion: If the car’s power supply or locking hardware is faulty, the doors may not respond even with a working fob.
Other factors
- Signal interference from nearby devices or operating beyond the system’s effective range
- Passive-entry (hands-free) system malfunction or settings disabled in the vehicle
- Environmental factors such as extreme temperatures or moisture affecting sensors
- In smartphone-app-based unlocking, issues with the app account or connectivity can also disable access
Conclusion: Range, settings, and environmental conditions can cause temporary or intermittent failures in keyless entry.
Quick DIY checks
Before calling for service, try these practical steps that resolve many everyday issues without professional help.
- Replace the battery in your key fob and test both buttons from near the vehicle
- Use a spare key fob if available to determine whether the issue is with the fob or the car system
- Check whether passive-entry or auto-unlock is enabled in the vehicle’s settings
- Attempt the manual key entry through the driver’s door to rule out a lock mechanism problem
- Inspect the fob and door handles for grime, moisture, or damage that could hinder signal transmission
Conclusion: If these steps restore function, you’ve identified the issue; otherwise, a deeper diagnostic is warranted.
When to seek professional help
If the problem persists across multiple doors or affects all fobs, professional diagnosis is advised. It can involve vehicle software, hardware, and recalls.
- Contact your dealer or a licensed automotive locksmith to check for recalls and to reprogram fobs if needed
- Have the fobs tested by a technician to confirm programming and battery integrity
- Ask a technician to inspect fuses, the central locking module, and the receiver/antenna for the doors and trunk
- Have the vehicle battery and charging system evaluated, since a low voltage can disrupt the keyless system
- In some cases, request a software update or module replacement if the fault lies in the car’s electronics
Conclusion: A professional assessment isolates hardware or software faults and guides appropriate repair or programming decisions.
Summary
Keyless-entry failures are most commonly caused by a dead key fob battery, followed by a weakening car battery or the need to re-sync. Less common causes include damaged fobs, wiring faults, or a faulty receiver or control module. Start with battery changes and simple re-sync attempts, then pursue professional diagnostics if the issue persists or affects multiple entry points. If relevant, check for recalls and updates through your manufacturer or dealer.
Why won't my keyless entry unlock my car?
Check the vehicle's receiver module for faults or interference. Ensure the keyless entry system's antenna is functioning properly. Sometimes, a software update at the dealer can resolve communication issues. Replace the key fob's internal circuit board if reprogramming fails.
How much does it cost to fix a keyless entry?
Average Key Fob Replacement Costs in 2024
| Type of Service | Estimated Cost (USD) |
|---|---|
| OEM Key Fob Replacement | $150 – $500 |
| Smart Key or Proximity Fob Replacement | $250 – $600 |
| Key Fob Programming at Dealership | $50 – $150 |
| Locksmith Programming Service | $30 – $100 |
Why did my keyless entry stop working?
Check the Car's Battery: If your car's battery is low or dead, the keyless entry system may not function properly. Charge or replace the battery and test the key fob again. Inspect the Keyless Entry System: If the car's battery isn't the issue, the problem could be with the keyless entry system's wiring or receiver.
What is the lifespan of a keyless entry?
5–7 yearsAverage Lifespan of Electronic Locks
| Type of Electronic Lock | Average Lifespan |
|---|---|
| Basic Keypad Lock | 5–7 years |
| RFID/Keycard Lock | 7–10 years |
| Biometric Lock | 8–10 years |
| Smart Lock (Bluetooth/Wi-Fi) | 5–8 years |
