An introduction to automobile transponder keys

11 August 2017
 Categories: , Blog


If you drive a car manufactured within the last few decades, you almost certainly use an electronic transponder key. These simple devices have contributed to a significant decline in Australia's vehicle theft rate, but most don't really know how they work or what to do if they need one replaced. 

What is a transponder key? 

The transponder located in your car's key fob is only half of the electronic system that keeps your car safe. The other half is the immobiliser, a device fitted to the car's engine. When you insert your key into the ignition, the car sends an electronic signal to the transponder, which then replies with an access code. If there is no reply, the immobiliser prevents the engine from starting. Thanks to the immobiliser, even if someone bypasses the ignition or uses a duplicate key, the car won't start unless the transponder is present. 

Effects of transponder keys

Transponder keys and other types of vehicle immobilisers have significantly reduced vehicle theft rates in Australia. Studies have shown that vehicles without immobilisers are several times more likely to be stolen than vehicles which have immobilisers.  Transponder keys are therefore a significant improvement to your car's security. This important role in deterring theft is why immobilisers are required on recent vehicles sold in Australia.

Replacing a transponder key

Electronic keys and immobilisers have improved automobile security in Australia, but the increased safety comes at a cost -- literally. Losing a transponder key or having it stolen can be much more costly than replacing a simple mechanical key. It can also take longer, as the new transponder and the immobiliser need to be properly configured. Most people who lose a transponder key immediately contact their car dealer, who will usually be able to replace the lost key. However, this isn't the only possible approach. An auto locksmith can replace most auto transponder keys, typically at a lower price than dealerships will charge. If your car keys are lost or stolen -- or if you just want to create a duplicate -- a car locksmith can help provide the replacement you need. 

A transponder key is a vital part of your vehicle's security system, making it much harder to steal. However, the increased expense and inconvenience involved in losing these keys means you should take extra care with them. Should you lose your key, an auto locksmith may be able to replace it for less than your dealer can.