Cruise Control not Working (Diagnosis and Troubleshooting)

What makes cruise control not work?

Bad brake pedal/light switch — This means communication between you, cruise control and the car is interrupted, and you can’t have immediate manual control of the car.

Bad fuse — Fuses blow to protect the electrical system. Cruise control fuses will do the same, to protect the system and circuits in your car the fuse will break and then need repairing.

Failing speed sensor — Speed sensors are important in cruise control because your car needs to remain at the same speed consistently. Broken speed sensors will affect more than cruise control and need to be serviced urgently

Bad actuator vacuum, hose, or cable –The actuator vacuum is what connects and activates the throttle control. The fault may be with the hoses in the vacuum actuator or the cable linking the system together.

Symptoms of bad cruise control switch

  • Symptom 1 — brake pedal does not disengage cruise control

There’s a switch fixed to the bases of the brake pedal and if cruise control does not deactivate when braking then it’s a sign that this switch is faulty.

  • Symptom 2 — Hissing noises are heard from under the dash.

The cruise control switch is a vacuum system and for some vehicles, it is mounted near the brake pedals under the dash. If you can hear hissing, it could indicate that the switch or one of the switch’s vacuum hoses is broken.

  • Symptom 3 — The cruise control switch/button itself does not work

When trying to turn on the function or while cruising it turns off, this is an indicator of a faulty switch and can be related to wiring issues or the above (1-2) symptoms

  • Symptom 4 — A blown fuse

A blown fuse could be a simple error and fix. The switch circuit or fuse may just need to be replaced for the problem to resolve.

Possible Cruise control failure Scenarios

1. Cruise control not working after battery change

  • Possible cause — This differs from vehicle to vehicle and among brands. Some drivers’ cruise control malfunctions after jump-starting their battery, and this is because the battery is still discharged. Newer cars have many electronic systems, and most are powered by the battery. So, if the battery is discharged or low-powered, the electrical cruise control system can be affected.
  • Solution — Putting your battery on a trickle charger (2-5 amp) for 12 hours or driving on cruise for a couple of hours may resolve this issue.

2. Cruise control turns off while driving

  • Possible cause — Damaged speed sensor or actuator, these two could be internally malfunctioning and causing the cruise control to disengage without input from you.
  • Solution — Have a technician or mechanic run a diagnostic with the speed sensor and check the actuator hoses and cables.

3. Cruise control works intermittently

  • Possible cause — this may relate to the brake pedal switch. If cruise control is intermittently disengaging, it could be a wiring issue with the switch.
  • Solution — Have the brake pedal to cruise control switch investigated by a mechanic or technician and determine if there is a faulty wire to blame. You may need to have the switch or some of its parts replaced.

4. Cruise control turns on but will not set

  • Possible cause — The brake pedal switch may be the issue. The brake pedal deactivates cruise control and if it is stuck in the open position, it may cause the cruise control to not engage or set properly.
  • Solution — Ask your mechanic or technician to check for this issue specifically in their diagnostic and service.

5. Cruise control turns on by itself

  • Possible cause — There may be a failure with the Electronic Control Module (ECM) which manages the actuators or Electronic Control Unit (ECU) which controls the speed in your cruise control
  • Solution — You could attempt to reprogram the ECU and ECM if you have the computer tools, otherwise take it into a trusted mechanic or technician.

There are many helpful forums run by mechanics and amateurs:  These are always great for solving those specific problems you might experience.

When CC does not set:

When CC is faulty after battery change:

For cruise control and other general repairs, watch this channel:


Can cruise control cause check engine light?

When the check engine light or MIL (Malfunction Indicator Light) is on, the cruise control light may blink to signal that cruise control has been disabled. This is a safety control as the vehicle is programmed to not go on ‘autopilot’ should the engine or mechanical issue relate to the cruise control systems. If the error or fault is with the cruise control systems, then the MIL may be lit for that as well.

How much does it cost to fix cruise control malfunctions?

  • For switch repair (parts and labour) it’s estimated at $125- $350
  • For fuse repairs, it could be up to $10 to buy the fuse and replace it yourself in a few minutes — there are many helpful YouTube tutorials on simple car repairs like this one.
  • For actuator repairs, some cost more than $700
  • Therefore, it’s important to know WHAT the issue is to get an idea of HOW MUCH it will cost you.

Does cruise control malfunction trigger the check engine light?

The function of a check engine light or MIL (Malfunction Indicator Light) is to communicate engine or mechanical failures in your vehicle to prevent an accident on the road. The MIL can be lit for simple reasons like the gas cap is loose. Should your CC system fail or run incorrectly, the MIL could light up. Often when there are other failures or engine faults, the MIL will light and the cruise control with a flicker to signal it has been disabled for safety reasons. Once the cruise control or other issues are fixed, all the lights should go back to being turned off.

Author: DJ

Dave Junior is a hands-on automotive technician with experience in performing service, diagnostics, and repairs on domestic and imported vehicles. He enjoys writing and sharing his knowledge far and wide.

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