2009 Toyota Prius Cruise Control Isn't Working

Common Causes of Cruise Control Malfunctions in Your 2009 Toyota Prius and How to Fix Them

Find Repair Location
Reviewed by
Bo Fader
Written by RepairPal Car Genius
Updated January 14, 2025
0%
30% chance it's the
Sensor
0%
25% chance it's the
Control Module
0%
25% chance it's the
Throttle
0%
20% chance it's
Something else
The most common reasons a 2009 Toyota Prius cruise control isn't working are failed control module, sensor or switch issues, or throttle actuation problems.
  • Sensor: A faulty or malfunctioning sensor can lead to incorrect readings, causing issues with engine performance or other systems relying on accurate data.
  • Control Module: A faulty control module can lead to erratic vehicle behavior or failure of various electronic systems due to improper signal processing.
  • Throttle: A faulty throttle body or a defective accelerator pedal position sensor may be causing inconsistent throttle response.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2009 Toyota Prius cruise control isn't working?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

In the event that a wheel speed sensor fails, the ABS, traction control system (TCS) and manufacturer specific stability control system lights will illuminate, informing the driver that the systems are disabled. The vehicle will be more prone to tire slip, and normal driving patterns may need to be adjusted to correct for the loss of computer control. On older vehicle's, the speedometer can be affected, causing illumination of the check engine light as well.

The cruise control switch can cause complete failure of the cruise control feature, but in a lucky scenario only partial functionality will be lost. This means that the cruise control may come on, but that it will not increase in speed automatically, or the cancel button does not work leading the driver to cancel cruise control with the foot brake. In some vehicles, the cruise control light may illuminate, or a warning message may be displayed due to lack of functionality.

What are the steps to diagnose the cruise control issue in a 2009 Toyota Prius?

To effectively diagnose a cruise control issue in a 2009 Toyota Prius, it's essential to adopt a systematic approach that begins with the simplest checks before progressing to more complex diagnostics. Start by inspecting the cruise control fuse, as a blown or damaged fuse can easily disrupt the system's functionality. Next, examine the cruise control buttons on the steering wheel to ensure they are operational and not stuck, as this can prevent engagement. Utilizing an OBD-II scanner to check for error codes can provide valuable insights into any underlying issues. The vehicle speed sensor is another critical component; ensure it is functioning correctly, as it directly affects cruise control performance. Additionally, inspect the brake light switch, since a malfunction here can inadvertently disable the cruise control. If these initial checks do not reveal the problem, proceed to test the cruise control module for proper signal transmission. Lastly, inspect all related wiring and connections for any signs of damage or corrosion. If the issue remains unresolved after these steps, seeking assistance from a professional mechanic is advisable to ensure a thorough diagnosis and repair. This methodical approach not only helps in identifying the problem efficiently but also saves time and resources in the DIY process.

What are the common problems that could cause the cruise control to stop working in a 2009 Toyota Prius?

When dealing with cruise control issues in a 2009 Toyota Prius, it's essential to understand the common problems that may be at play. One frequent culprit is a faulty brake light switch, which can prevent the cruise control from engaging since it is designed to deactivate when the brakes are applied. Additionally, speed sensor issues can disrupt the system's ability to maintain a constant speed, leading to cruise control failure. Another potential problem is a blown fuse within the cruise control system; checking and replacing this fuse can often resolve the issue. Furthermore, a malfunctioning throttle actuator may hinder the cruise control's performance by affecting engine speed control. Lastly, problems with the Electronic Control Module (ECM) can also impact the cruise control system, as this computer manages various vehicle functions. By systematically checking these components, DIYers can effectively troubleshoot and potentially restore functionality to their Prius's cruise control system.

How urgent is it to address the malfunctioning cruise control in a 2009 Toyota Prius?

Addressing a malfunctioning cruise control in a 2009 Toyota Prius is of utmost urgency due to the significant safety risks it poses. A faulty system can lead to unexpected acceleration or deceleration, which can result in dangerous driving situations and increase the likelihood of accidents. Moreover, when cruise control fails, drivers may find themselves constantly adjusting their speed manually, leading to fatigue and distraction, which further compromises road safety. Additionally, neglecting this issue can lead to increased fuel consumption and potential damage to the vehicle's engine and other components, ultimately resulting in costly repairs. Therefore, it is crucial for Prius owners to prioritize the repair of their cruise control system to ensure not only their safety but also the longevity and performance of their vehicle.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.