Original articles can be found on the MyBroadBand website.

Car remote jamming is an easy attack would-be thieves use to prevent drivers from locking their vehicles in parking lots around South Africa.

While this relies on victims not noticing their car didn’t lock, car jamming is easy enough that finding the right target doesn’t cost much.

Criminals don’t need illegal instruments or technical expertise to get started – all they need is a gate or garage remote with a sufficiently-powerful transmitter that operates on the same frequency as your car remote. One such frequency band for remote controls is 433MHz.

A gate remote that puts out a powerful signal on the same frequency as your car remote can easily “drown out” the message to lock or unlock the doors.

Watch real-life car remote jamming criminals in action

Drivers who don’t have jamming detectors will have to take other precautions to ensure they don’t fall victim to remote jamming. Most importantly:

  • Manually check that your car is locked before walking away.
  • Never leave valuables in your car.

How car remote jamming works

Fouche Burgers from Business Against Crime SA explained that criminals can block, or jam, the locking signals of remote locking devices on vehicles.

Most modern remote controls use rolling-code technology, which means that the code command cannot be copied or cloned.

However, because most modern remote controls work with radio waves that use an allocated radio frequency, they are vulnerable.

The use of this specific radio frequency is prescribed by Icasa.

Most remote controls, including those for motor vehicles, gate, and garage automation operate on a frequency of 433MHz. Understandably, this frequency has become very busy.

When a remote control button is pressed, it sends a message (command) on the allocated frequency to a receiver (in the vehicle) to perform an action: lock or unlock the vehicle.

At the other end, the receiver is “listening” for a specific message that it can interpret to perform a required action.

When a button of another remote is pressed in close proximity, the receiver receives (hears) two messages simultaneously.

The two messages are consequently scrambled, the receiver cannot interpret the message, and no action is initiated (the vehicle’s doors are not locked).

Remote controls operating on the same frequency can influence each other’s messages if they are operated in close proximity.

According to Outsurance, thieves often use a standard 400MHz gate or garage remote control to jam the signal sent by a car remote control.

To make matters worse, there are “professional” jamming devices available that function on a range of frequencies and that have much higher signal power.

These devices can influence a vehicle’s remote control from a much greater distance and can even interfere with remote controls that use different frequencies and technologies.

It should be noted that these remote control and jamming devices cannot unlock your vehicle. They can only stop your remote control from working properly.