Stay in Control: Your Vehicle’s Cruise Control System

If you are lucky enough to have cruise control in your vehicle, you already know the added benefit of using it when driving on those long, open highway hauls. Cruise control helps you regulate a specific driving speed, improves your overall gas consumption, and in newer models can actually keep you safely distanced from other vehicles. Read on to learn more about the basics of how a cruise control system works and the typical problems that may arise with your cruise control.

Cruise Control Basics

Believe it or not, modern cruise control was invented in the late 1940s.  Over the last eighty years, cruise control has evolved into a component of your vehicle that functions mainly through the use of cables and actuators, or in newer vehicles, wireless technology.Conventional cruise control systems are designed to mimic what you do as a driver – control the acceleration of the vehicle.Here’s how a conventional cruise control system works:

  1. Using the controls on the steering wheel during operation, a driver engages the cruise control system and sets the desired vehicle speed.
  2. Once the speed is set, the cruise control maintains the speed through the use of a cable that is connected to the throttle body.  The cable is powered by an actuator, giving it movement to control the airflow to the engine and speed it up or slow it down.
  3. Newer vehicles use wireless technology to send the signals to the vehicle’s computer, controlling the speed of the vehicle.  Some newer cars also have a feature called adaptive cruise control, which is an additional feature of the system that enables you to maintain a safe distance from the vehicle in front of you through the use of laser and radar technology.
  4. Note:  A safety feature of all cruise control systems is the deactivation of the system when the driver depresses the brake pedal, giving acceleration control back to the driver.

Cruise Control Problems

The majority of us are not thinking about how our cruise control works when we hit the ON or SET buttons – we are just hoping to “set it and forget it.”  While the cruise control component of our vehicle is not something we would normally think of malfunctioning – it is still susceptible to breakdown.

Unfortunately, cruise control systems are not the type of engine component that can receive regular maintenance, so you most likely will only find out about your malfunctioning system when it no longer works. However, you will see that other systems in the vehicle can affect the ability of the cruise control to work properly. That means maintaining all the vital components of your vehicle on a regular basis.

So, what are some of the reasons why your cruise control will not operate effectively or at all?

  • Brake Lights/Switch:  Since the cruise control is disabled by depressing the brake pedal, if the system is unable to detect the brake light switch, it may not function.  Additionally, if a brake light is blown or the vehicle has LED lighting, it may not send the proper signals to operate the cruise control system. Make sure your brakes are maintained regularly.
  • Faulty Fuse or Relay:  If the fuse that protects the actuator is blown or there is a faulty relay, this may prevent the cruise control from working.
  • Faulty Controls:  There are several ways the actual in-cabin controls can affect your cruise control operation.  Faulty cables or switches may not activate the cruise control mechanisms.
  • Vacuum Leaks:  Older cruise control systems use a vacuum actuator to control the throttle.  If there is a leak in the vacuum, the cruise control will not operate.
  • Check Engine Light:  Some vehicles are equipped to disable the cruise control if there is a possible problem with the engine or transmission.  Have all Check Engine problems diagnosed and fixed promptly.
  • Vehicle Speed Sensor:  If the vehicle speed sensor is unable to detect the vehicle speed or send that information to the cruise control for any reasons, it will disable the cruise control.

If you are experiencing a malfunctioning cruise control, contact Shade Tree Garage in Morristown, NJ, today to schedule a professional inspection of your system.  We will go over the system and provide you with recommendations on the necessary repairs to keep your cruise control system running smoothly.