What is a Transponder Key?

Almost all new cars on the road today use a transponder key. These are devices that are designed to
transmit a signal from your key to a remote receiver. While most commonly used to unlock and start vehicles, they are also used in devices like keyless entry systems and garage door openers. Transponders are programmed to start a particular vehicle which reduces the possibility of theft.

What is a transponder?

Transponder stands for transmitter + responder; it is a radio frequency device that transmits an electronic signal to another radio frequency device. The transmitter is a small microchip with a unique serial number in the plastic part of the key. This serial number is set during initial programming. There is a device near the ignition switch has the receiver. The key transmits a low-level signal that the vehicle can detect when the key is in the switch.

The small chip in your automobile receives a signal from your vehicle. If the corresponding key to the computer is not used in the car, it won’t find the correct serial number, and it will not start. The vehicle’s computer needs to receive the proper response from the transponder key. If it doesn’t, the computer will not allow the vehicle to operate.

A transponder key is a part of the car’s anti-theft system and prevents the car from being hotwired since if the device in the key isn’t detected, the car won’t start.

How do you get a copy of your car key if it has a transponder?

Most transponder keys need to be programmed to your car or cloned from an existing key for your vehicle to accept it. You can see a locksmith since they will have the equipment and expertise to make a copy of your key that works. Transponder keys are more expensive than getting a regular key because of the programming involved. While replacing or making a copy of the key will be more expensive, it is typically more affordable through a locksmith than through the dealership.

For more information about transponder keys contact Bedford Lock & Key at 781-275-1597 in Bedford, MA or 978-433-5262 in Pepperell, MA.