With the consumer’s increased priority for automotive technology, advanced car technologies may cross some new boundaries but the safety element will always remain present. Consumers not only demand for autonomous technology but also for the one which is safer and more reliable means of transportation. Manufacturers of many vehicle brands including BMW have thus incorporated driver-assistance and other safety features to make their vehicles up to the mark to meet these consumer demands. Active cruise control is one such system.

What is Active Cruise Control System?

BMW Active Cruise Control Failure Explained

Active cruise control on your BMW is an advanced driver-assistance system that automatically adjusts the vehicle speed at a certain distance from other vehicles on the road to maintain safety. It is also known as adaptive cruise control or dynamic cruise control. Its main function is to help driver maintain a safe following distance and stay within speed limits by adjusting automatically without requiring driver to do so.

How does it work?

Active cruise control system works with sensory technologies installed within the vehicles such as radar, cameras, laser equipments as well as navigation system data. This sensory technology creates an idea of how close one car is to another or other objects on the road. Using car’s navigation system, it adapts the speed ahead of bends, roundabouts and junctions. It allows the car to detect and warn the driver about potential forward collisions.

When this happens, red lights begin to flash and dashboard displays a message of “Brake Now!” to help the driver slow down. You have to set a speed and a desired distance before driving the car. Controls to increase or decrease speed are given on the left side of the steering wheel and distance is visible on the dashboard. Having a safety feature controlled during your drive is most important to take advantage of driver-assistance technology.

What is the error?

Risks are minimized with these active safety features installed and activated but sometimes, they might stop working for different reasons that will be explained later in the blog and a warning message pops up on your dashboard pointing to the failure of Active cruise control.

Most common warning messages you might receive on BMW dashboard:

  • Cruise Control failure
  • Active Cruise Control Failure.
  • Keep your distance!

Why it happens and how to fix this error?

Now, what are the reasons that affect the functionality of active cruise control system? One of the most common reasons is the sensor failure. While assuming that it is a component which may fail due to completion of its life we shouldn’t forget its location. Since it locates at the front and in some specific weather conditions such as snow, fog, rain, it may catch some of the moist and stop responding. It is also possible that a carrier bag is stuck on the front preventing it to have a clear view. Simple checking for any debris or moisture on the sensor and cleaning it off should give a vent to this message off.

However, if this doesn’t resolve the error, then check for the alignment of the sensor. Maybe your car had collided somewhere and while no visible damages are observed, sensor would have moved from its place. And because sensor is located in or behind the front bumper/griller, it is uncommon for a person to check it for its placement. But, this time try to reach through it and accurately place it in its position. Proper positioning is the real idea for an active cruise system to work accurately.

If error persists, and nothing mentioned above works, though it happens only in rare situations then you might need to update the software for error to get disappear. This is a good idea at least before investing into replacing new radar sensor.

If you’ve tried every trick and none of them did any good to fix this error then consider replacing the sensor with a new one.  It is suggested that you take your car to the dealer for replacement such as xenosn4u where you will find radar sensor as well as the satisfied replacement services but if you want to do it by yourself then follow the instructions:

  • De-activate the active cruise control system of your BMW before replacing radar sensor
  • During replacement, if you feel any debris or moisture on connectors or wires then keep calm, radar sensor was hit affected by these external factors. Simply wipe out them before installation of a new radar unit.
  • After reinstallation or replacement, your BMW may need calibration with a scan tool. Make sure you calibrate it before returning to the active cruise control status.

In the most extreme cases, you can choose to keep Active Cruise Control system deactivated, which means your BMW will no longer control the distance between vehicles. To do so press and hold one of the distance control buttons to deactivate Active Cruise Control. But, it is highly not recommended because a feature that may call upon safety of you and others on road should always be remaining operative.