Cruise control stops working for a handful of common reasons, most of which you can diagnose yourself before calling a mechanic
Cruise control fails when the switch is broken, the fuse has blown, the brake pedal sensor is stuck, or the vehicle's computer has lost the signal from one of its sensors. Some of these you can fix in minutes. Others require a mechanic, but knowing which category your problem falls into saves you a diagnostic fee and tells you whether the repair will be straightforward or involved.
Start by checking whether the system is actually off or whether something is preventing it from engaging. Then work through the electrical and mechanical checks in order. Most people find the problem before they need to open the engine bay.
Key Takeaways
- Cruise control won't engage if the brake pedal sensor is stuck, the fuse has blown, or the on/off switch is faulty—all things you can check yourself.
- A blown fuse is the fastest fix: locate your fuse box (usually under the dashboard or hood), find the cruise control fuse, and replace it with an identical amperage.
- If the brake pedal feels soft or spongy, or if cruise control disengages the moment you touch the brake, the brake sensor may need adjustment or replacement by a mechanic.
- Modern vehicles store fault codes when cruise control fails; a mechanic can read these codes in seconds and pinpoint the exact problem.
- If nothing works and the vehicle is still under warranty, the repair is usually covered—check your owner's manual for the warranty period.
Check the fuse first
A blown fuse is the most common reason cruise control stops working, and it is the easiest to fix. Your vehicle has a fuse box—usually located under the dashboard on the driver's side, or under the hood near the battery. Check your owner's manual for the exact location and the fuse diagram.
Open the fuse box cover and look for the cruise control fuse. The diagram will tell you which slot it occupies and what amperage it should be (typically 10 or 15 amps). Pull the fuse straight out. If the wire inside is broken or blackened, it has blown. Buy an identical replacement at any auto parts store—they cost a dollar or two—and push it firmly into the slot until it clicks.
Turn on the ignition and test cruise control. If it works, you are done. If the new fuse blows when ready or within a few days, there is a short circuit in the cruise control wiring, and you need a mechanic.
Test the cruise control switch
The on/off switch is usually on the steering wheel or a stalk below it. Press it and listen for a click. If you hear nothing, the switch may be broken internally. Some switches can be cleaned if they are straightforward stuck with dust; others must be replaced.
If the switch clicks but cruise control still will not engage, move to the brake pedal sensor. The switch itself is rarely the problem unless it is visibly cracked or the button does not move smoothly.
Check the brake pedal sensor
Cruise control disengages whenever you touch the brake pedal because a sensor under the pedal tells the system to shut off. If this sensor is stuck in the "pressed" position, cruise control will not engage at all—the system thinks you are always braking.
Sit in the driver's seat with the engine off. Press the brake pedal all the way down, then release it slowly and listen for a click near the pedal. You should hear a distinct click as the pedal returns to rest. If you hear nothing, or if the pedal feels soft or spongy, the sensor may be stuck or the brake fluid may be low.
Check your brake fluid level first. Open the hood and locate the brake fluid reservoir (a translucent plastic tank near the back of the engine bay). The fluid should reach the "full" line. If it is low, top it up with the correct brake fluid type from your owner's manual, then test cruise control again.
If the fluid is full and the pedal still feels soft, or if you hear no click, the brake sensor needs adjustment or replacement. This requires a mechanic.
Look for loose or corroded connections
Corrosion on battery terminals or loose ground wires can prevent cruise control from working even if everything else is fine. Open the hood and inspect the battery terminals—the metal posts where the cables connect. If they are white, blue, or green, they are corroded.
Disconnect the negative cable (black) first, then the positive cable (red). Clean both terminals and the inside of the cable connectors with a wire brush or steel wool until the metal is shiny. Reconnect the positive cable first, then the negative. Tighten both connections firmly.
Also check that the ground wire—usually a black or brown cable bolted to the engine block or frame—is tight and free of corrosion. A loose ground can cause electrical gremlins throughout the vehicle.
Read the fault code if the vehicle is modern
Most vehicles made after 2000 store a fault code when cruise control fails. You cannot read this code without a scanner, but any mechanic can do it in seconds—many will do it for free or for a small diagnostic fee. The code tells you exactly which sensor or switch has failed, which saves time and guesswork.
If you own a scanner or know someone who does, you can read the code yourself. Connect the scanner to the diagnostic port under the steering column, turn on the ignition, and follow the scanner's menu. Write down any code that starts with "P" and contains "cruise" or "speed control." Show this code to a mechanic, and they will know what to replace.
When to call a mechanic
Call a mechanic if the fuse is not blown, the switch clicks, the brake pedal sensor clicks, and the battery terminals are clean. At that point, the problem is either a wiring fault, a faulty speed sensor, or a computer issue—all of which require diagnostic equipment.
Also call a mechanic if the brake pedal feels soft or spongy, because that indicates a brake system problem that affects safety, not just cruise control. Do not drive the vehicle until the brake system is inspected.
If your vehicle is still under warranty, contact the dealership instead of an independent mechanic. Cruise control repairs are usually covered, and the dealership can access the manufacturer's technical bulletins, which sometimes describe a known issue and a quick fix.
Frequently Asked Questions
Can I drive without cruise control while I wait for a repair?
Yes, cruise control is a convenience feature, not a safety system. You can drive normally using the accelerator pedal. However, if the problem is a faulty brake sensor, have the brakes inspected before driving, because the sensor failure may indicate a brake system issue.
Why does cruise control disengage the moment I touch the brake?
That is normal—cruise control is designed to shut off when ready when you touch the brake pedal. If it disengages when you are not touching the brake, the brake sensor is stuck or faulty and needs replacement.
What does it cost to replace a cruise control switch or sensor?
A switch replacement typically costs between $100 and $300 in labor and parts. A brake sensor replacement usually runs $150 to $400. Prices vary by vehicle make and whether you go to a dealership or an independent shop. Ask for a quote before authorizing work.
Will a blown cruise control fuse affect anything else in the vehicle?
No, the cruise control fuse only protects the cruise control circuit. If it blows, only cruise control stops working. Other electrical systems are unaffected.
Is cruise control worth fixing, or should I just leave it broken?
That depends on how much you use it. If you spend a lot of time on highways, fixing it improves comfort and reduces fatigue. If you mostly drive in the city, it is less critical. A blown fuse is always worth replacing because it costs almost nothing. For a switch or sensor, weigh the repair cost against how much you would use the feature.