Nobody likes it when their cruise control stops working.
The whole point it was created was to reduce the stress put on drivers who are on the road for an extended amount of time. If it doesn’t work, it can be bothersome and a pain in the butt.
Beyond that, it can be dangerous as well.
That’s why it’s important to understand how cruise control works and what the reasons it may stop functioning are.
Let’s dive in.
Understanding How It Works
Cruise control works to keep your vehicle’s speed at a consistent level that you set.
You can do this simply by engaging the cruise control on one of the buttons in your vehicle and then setting the cruise control with the most appropriate method for your vehicle.
Once set, you’ll be cruising along the highway without having to constantly keep your foot at just the right spot to keep your desired speed.
Cruise control has also evolved with modern times, you’ll often see adaptive cruise control systems. These systems use detection hardware, such as lasers or radars, to keep your vehicle at a safe distance from other objects.
While it may have evolved in some vehicles, that doesn’t make it any less dangerous to have malfunctioned.
Why Your Cruise Control Ceased Functioning
There are minor issues and major issues that would cause your cruise control to stop working. Some signs are easy to see while others may be more difficult.
In any case, it’s always important to make sure that your cruise control malfunctioning isn’t a symptom of an even larger problem.
We’ll start with some simpler issues that may be why the cruise control stopped working.
Bad or Failed Vehicle Speed Sensor
This is the main reason why cruise control modules may stop working.
While you may have multiple vehicle speed sensors on your vehicle, the cruise control module may take input from one, or more, sensors. These sensors can be from the electronic control module, the instrument cluster, or even from your transmission.
If your cruise control module fails to obtain the speed of your vehicle, it will disable itself to prevent any dangerous situations.
You should be able to tell if your vehicle speed sensor is having issues fairly easily. One of the first indicators of an issue is a check engine light that appears.
If you see a check engine light on and your cruise control stops functioning, you’ve more than likely found the issue. You will get error code P0501 when checking with bluetooth obd2 scanner. You should have one to check.
Broken Brake Lights
Some cruise control systems won’t work if a brake light is blown or not functioning correctly.
This is to ensure your safety as other cars on the road won’t be able to properly tell when you’re applying your brake pad.
In some cases, you may even find that aftermarket lighting may also confuse, or trick, your cruise control module into thinking that light is blown. This is because of the LED bulbs in aftermarket lighting, they draw less current than those of incandescent bulbs.
Check Engine Light
The check engine light can be a sign of many different problems, not just cruise control issues.
It can be a sign of something such as a vehicle speed sensor, a transmission issue, or an engine problem. Whatever the case may be, it has become increasingly popular for modern vehicle’s cruise control to stop functioning if the check engine light comes on.
Electrical issues are another prominent issue as to why your cruise control has stopped working properly.
You, or a professional, will need to dive deep into the nitty-gritty of the car and check the connectors, source voltage, and wiring harness. Something that has become unstable, broken, loose, or degraded could cause numerous issues – including disabling your cruise control.
If you suspect that electrical issues are the problem, do a thorough inspection to ensure that nothing else was affected as well.
Bad Brake Pedal Switch
If your brake pedal switch is failing, the car may misunderstand and think your brakes are engaged, which will then, in turn, disable the cruise control system.
This happens because cruise control systems are all designed to be turned off as soon as you press on the brake pedal, so you may slow down. The cruise control module will know you’re pressing the brake pedals because they’re directly connected.
If this is the case, your cruise control won’t work until you fix your brake pedal switch.
Blown fuses are the symptom of many problems, but it could be the direct reason for why your cruise control stopped working.
Many electronic systems within your vehicle use a fuse as a failsafe. When your vehicle detects a short circuit, it blows the fuse to protect the integrity of the rest of the vehicle.
This helps your vehicle, but may not help your cruise control.
If the fuse for the cruise control blows, then your ability to use cruise control will also go out the window.
A lot of older vehicles use vacuum actuators to help maintain the throttle body while the cruise control is working.
If a leak within these vacuums occurs, the system will fail to work. These leaks can be through a cracked tube or hose.
However, this problem will only rear its head in older vehicles. If you’ve kept up with modern technology, this shouldn’t be a problem for you.
Poor Cable Contact
Because of ease of use for the consumer, you’ll often find that vehicle mount the cruise control switch on the steering wheel. This means that a spiral cable is attached to the cruise control.
If this cable has an open circuit, it may prevent the switch from properly contacting the cruise control module.
If there is no contact, there is no input. Thus, your vehicle’s cruise control won’t function correctly.