Is It Possible for a Transponder Key To Fail

ADL-car keys on a table

In the constantly evolving world of automotive security, transponder key technology is essentially obsolete.

Nevertheless, this form of security protection is still utilized by many older vehicles on the road. As this type of technology inevitably begins to age, problems arise from years of normal wear and tear.

Occasionally, a transponder key can malfunction and cause problems for car owners. This is especially problematic because many transponder keys also serve as a car’s security feature; if your key malfunctions, you may risk yourself from being locked out.

Now that we know that transponder keys can malfunction let’s analyze why. Continue reading as we explain how transponder keys function and offer troubleshooting advice if your key malfunctions.

What is a Transponder Key

A transponder, which combines the words “transmitter” and “responder,” is set up to start a specific vehicle, which is essential for lowering the likelihood of auto theft. A tiny computer chip found in transponder keys emits a low radio signal. The original and duplicate car keys are verified by the microchip’s special digital serial numbers. Only when the key is in the ignition or close to the dashboard do the signals activate the chip.

When the ignition is turned on, an encoded message is sent to the transponder key by the Engine Control Unit (ECU). The original key will interpret the coded message and respond directly to the ECU. The car will start after the messages have been verified.

Can a Transponder Key Go Bad

Transponder key failure occasionally happens and causes problems for drivers. This is especially problematic because most transponder keys also serve as a car’s second line of defense in terms of security, which means that if your key fails, you risk being locked out or locked in.

Common Symptoms that Your Transponder Key is Malfunctioning

As helpful as transponder chip keys have been, they can cause issues in various ways. Here are some of the most common bad transponder key symptoms.

1. Locking and unlocking problems

If you use your transponder key to lock your vehicle remotely and it does not lock consistently, something is wrong. The same rule applies if you try to use the transponder to open a lock while inside the vehicle and it does not work. The former is particularly problematic in modern vehicles, which lack keyholes on the driver’s door.

If it does this several times before returning to normal operation, it is a clear indication that something is wrong and should be assessed immediately.

2. Engine doesn’t start.

If you turn the key in the ignition and nothing happens, the transponder chip key in your car may have lost memory of your key. This is different from engine issues because even though your engine won’t fully start, you will still hear a confirmation that it is starting. On the other hand, problems with the transponder key won’t have this sign.

3. Emergency signal malfunction.

The transponder keys in your car could malfunction if the distress signal or alarm goes off without warning or if you do nothing when it does. Using non-transponder keys to initiate the car’s warning system is possible in some cases. You’ll be alerted if anyone attempts to break into your vehicle using this extra security measure.

4. Key in the ignition doesn’t work.

If you put your key in the ignition, but the engine won’t start, it’s possible that the transponder chip in your vehicle no longer recognizes your key. In contrast to engine problems, you will still hear a confirmation that your engine is starting, even if it does not fully start. However, transponder key problems will not have this indication.

How to Fix Minor Issues

Often, you can resolve transponder key issues by simply changing the key fob’s battery. For many transponder keys to transmit the security code to the vehicle immobilizer, a tiny battery is required. To avoid unintentionally damaging the transponder chip inside, be cautious when changing the battery.

However, if you’ve changed the battery and it still isn’t working, the transponder chip may have been damaged somehow. In this situation, you must get in touch with your car dealership and ask for their transponder key programmer to check your unit.

Be prepared to spend a hundred to several hundred dollars on a transponder key replacement. In general, the cost of a replacement key fob is attributable to the vehicle’s value.

Best Practices to Safeguard Your Transponder Keys

  • Do not use the key to start the engine while the key ring is resting on the key grip or while pressing the key ring against the key grip. In such a case, the engine might not start or stop shortly after it does.
  • When starting the engine, do not use the key in conjunction with other transponder keys. Other vehicle keys are included.
  • Do not flex the key grip.
  • Please avoid using any material that blocks electromagnetic waves to cover the key grip because it shields or blocks radio frequency waves. Aluminum foil is an example of such a substance.
  • Avoid hard clashes between the key and other objects.
  • Avoid leaving the key out in the sun or on hot surfaces like the dashboard for an extended period.
  • Avoid immersing the key in water or using an ultrasonic washer to clean it.
  • Avoid using the key with items that use electromagnetic fields.


In conclusion, transponder keys provide a higher level of safety than traditional metal keys, but they are not without drawbacks. Just like anything else in life, there is no guarantee that it will work every time. Therefore, it would be best to enrich your knowledge regarding this matter. Consider all the information and tips mentioned above to make informed decisions when solving your transponder key issues when the time comes.

When all else fails, Alexius Denver’s Locksmiths will always be here to help.

If you’re encountering such transponder key issues, and you’ve tried everything in your knowledge to remedy the problem but to no avail. Maybe it’s time to let our professional locksmith in Aurora, CO, handle your transponder problems. With our years of expertise, you’re rest assured that we will deliver the highest quality of service that we can provide at affordable prices and guarantees. Contact us now.

Related Posts