How do I know if my cruise control fuse is blown?
If the cruise control won’t engage or the dash indicator isn’t showing, a blown fuse is a common and easily checked culprit. Locating the fuse, inspecting it, and replacing it with the correct rating can resolve simple failures. If the new fuse blows again, there’s likely a deeper electrical fault that warrants a professional diagnosis.
Signs the fuse could be blown
These symptoms can indicate a fuse issue rather than a fault in the cruise control system itself. Look for the following:
- The cruise control will not engage or stays off after pressing SET/RES.
- The cruise control indicator light on the dashboard does not illuminate when you turn the system on.
- Cruise control behaves erratically or disengages unexpectedly while driving.
- The fuse itself appears burnt, melted, discolored, or emits a burnt smell upon inspection.
Note: Even if the fuse looks fine, testing with a meter is the only reliable way to confirm whether it’s functional.
Where to find the cruise control fuse
Fuse placement varies by vehicle, but the cruise control fuse is typically located in one of two places: the interior fuse box under the driver’s dash or the engine compartment fuse box. Look for a label such as CRUISE, CC, CCP, or Cruise Control on the fuse diagram.
Common locations and labels
- Interior fuse box under the driver’s side dash
- Engine bay fuse box near the battery or firewall
- Fuses labeled CRUISE, CC, C/C, or Cruise Control; occasionally tied to a related circuit
- Some vehicles use a dedicated cruise control relay in addition to a fuse
Check the owner’s manual or the fuse box cover for the exact location and the specific amperage rating.
How to test the fuse
To confirm whether the fuse is truly blown, use one of these testing methods:
- Visual inspection: Remove the fuse and look for a broken internal conductor or scorch marks; replace if damaged.
- Continuity test with a multimeter: A good fuse shows continuity (low resistance); a blown fuse shows no continuity.
- Check the amperage rating and replace only with a fuse of the same rating; never substitute a higher rating to bypass a fault.
After testing, reinsert a good fuse and test the cruise control in a safe environment. If the fuse blows again, there is likely a short or fault in the cruise control circuit requiring professional inspection.
What to do if the fuse keeps blowing
Repeated fuse blows indicate an underlying electrical issue beyond a simple fuse swap. Follow these steps to address the problem:
- Turn off the ignition and, if you’re comfortable, disconnect the battery before handling fuses; otherwise ensure the ignition is off and the vehicle is in park with the parking brake applied.
- Replace the fuse with the correct amperage rating and re-test; do not drive with a known fuse issue.
- Inspect related wiring harnesses, connectors, and the cruise control actuator/servo for damage or short circuits.
- Check related safety interlocks such as the brake pedal switch and clutch switch, since these can disable cruise independently of the fuse.
- Seek a professional diagnosis from a dealer or qualified mechanic; use the service manual or OBD-II scan to identify fault codes.
If the fuse continues to blow after replacement, avoid continued use of cruise control and pursue a thorough electrical diagnostic to locate the fault.
Other common reasons cruise control stops working
Fuses are not the only potential cause. Other components can fail and prevent cruise control operation even when the fuse is intact:
Brake pedal switch and clutch switch
A faulty brake switch or clutch switch can prevent cruise control from engaging or re-engaging. The system is designed to disengage when you brake or shift out of drive.
Vehicle speed sensor and steering data
The cruise control relies on accurate speed input. A faulty wheel speed sensor or vehicle speed sensor can prevent maintaining target speed or prevent engagement altogether.
Cruise control module and wiring
A failed cruise control module, blown relay, or damaged wiring harness can cause intermittent or permanent failure independent of the fuse.
Vacuum lines and servo (older cars)
In older models that use a vacuum-operated cruise control, leaks or diaphragm failure can stop the system even if the fuse is fine.
Summary
To determine whether the cruise control fuse is blown, inspect the fuse visually, test for continuity with a multimeter, and replace with the correct rating if necessary. If the new fuse blows again, there is likely a short or fault in the cruise control circuit and a professional diagnosis is advised. Always refer to your vehicle’s manual for the exact fuse location, rating, and wiring diagrams, and prioritize safety when performing any under-dash work.
