2005 Lexus IS300 Cruise Control Isn't Working

Common Causes of Cruise Control Malfunctions in Your 2005 Lexus IS300 and How to Fix Them

Find Repair Location
Reviewed by
Andrew Hajjar
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 2005 Lexus IS300 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 2005 Lexus IS300 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.

When the vehicle speed sensor fails or the wiring harness prevents signal transmission, the speedometer is the first thing that will stop functioning properly. This can be an intermittent issue where the speedometer only works occasionally, the speedometer may cease all function, or the speedometer may read erratically or incorrectly. Also, the traction control and anti lock brake warning lights specific to each vehicle may be illuminated, depending on the design of those systems. You may notice the vehicle hesitate to accelerate, cruise control will not function properly, and the vehicle may not shift properly through all of the gears.

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 2005 Lexus IS300?

To effectively diagnose a cruise control issue in a 2005 Lexus IS300, start with the simplest solutions before moving on to more complex diagnostics. Begin by checking the cruise control fuse, as a blown fuse can easily disrupt functionality. Next, inspect the cruise control buttons on the steering wheel for any signs of sticking or malfunction, as these can prevent the system from engaging properly. If these initial checks do not reveal the problem, use an OBD-II scanner to look for error codes that may indicate specific issues within the cruise control system. Following this, examine the cruise control module for any visible damage or loose connections, ensuring everything is securely attached. Testing the cruise control actuator is also crucial, as it plays a key role in maintaining speed. Additionally, verify that the vehicle speed sensor is functioning correctly, as a faulty sensor can lead to cruise control failures. If these steps do not resolve the issue, it may be time to consult a professional mechanic who specializes in Lexus vehicles for further assistance. By following this structured approach, you can systematically identify and address the cruise control problem in your Lexus IS300.

What are the common problems that could cause the cruise control to stop working in a 2005 Lexus IS300?

When troubleshooting the cruise control system in a 2005 Lexus IS300, it's essential to consider several common problems that may be at play. Start by checking the cruise control switch, as a faulty switch can prevent the system from engaging or disengaging properly. Next, inspect the fuses related to the cruise control; a blown fuse can disrupt the entire system's functionality. Additionally, look for vacuum leaks in the engine, as these can hinder the cruise control's ability to maintain speed. The speed sensor is another critical component; if it's defective, it can lead to erratic speed regulation. Don't overlook the brake light switch, as issues here can cause the cruise control to disengage unexpectedly when the brakes are applied. Lastly, examine the throttle cable for any malfunctions, as this can affect the system's ability to adjust speed accurately. By systematically checking these components, you can identify and potentially resolve the issue with your cruise control system.

How urgent is it to address the non-functioning cruise control in a 2005 Lexus IS300?

When it comes to the non-functioning cruise control in a 2005 Lexus IS300, understanding the urgency of the situation is crucial for any DIY enthusiast. While this issue may not pose an immediate safety risk like malfunctioning brakes or engine problems, it can still significantly impact your driving experience. A malfunctioning cruise control system can lead to increased driver fatigue during long trips, as you may find yourself constantly adjusting your speed. Additionally, without cruise control, you may inadvertently drive at inconsistent speeds, which can affect fuel efficiency and lead to unnecessary wear on your vehicle. Therefore, while it may be tempting to delay repairs, addressing the cruise control issue promptly can enhance your comfort and convenience on the road. Moreover, diagnosing and fixing the problem early can prevent further complications that might arise from neglecting the system, ensuring that your vehicle remains in optimal condition for all your driving needs.

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.