2001 Mercedes-Benz ML320 Cruise Control Isn't Working

Common Causes of Cruise Control Malfunctions in Your 2001 Mercedes-Benz ML320 and How to Fix Them

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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 2001 Mercedes-Benz ML320 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 2001 Mercedes-Benz ML320 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 2001 Mercedes-Benz ML320?

When diagnosing a cruise control issue in a 2001 Mercedes-Benz ML320, it's essential to adopt a systematic approach that begins with the simplest solutions before progressing to more complex diagnostics. Start by checking the cruise control fuse, as a blown fuse can easily disrupt the system's functionality. Next, inspect the cruise control buttons on the steering wheel to ensure they are operational, since faulty buttons can lead to engagement problems. Utilizing an OBD-II scanner to scan for error codes is a crucial step, as it can reveal specific issues affecting the cruise control system. Following this, verify the functionality of the vehicle's speed sensors, which are vital for the cruise control to operate correctly. Additionally, examine the brake light switch, as a malfunction here can prevent the cruise control from engaging altogether. Finally, test the cruise control module to confirm it is sending the appropriate signals. By following this diagnostic approach, you can effectively identify and address the underlying issues affecting the cruise control system in your vehicle.

What are the common problems that could cause the cruise control to stop working in a 2001 Mercedes-Benz ML320?

When dealing with a malfunctioning cruise control system in a 2001 Mercedes-Benz ML320, it's essential to understand the common issues that may be at play. One of the primary culprits is a faulty brake light switch, which can prevent the cruise control from engaging since it is designed to deactivate when the brake pedal is pressed. Additionally, vacuum leaks within the system can disrupt the cruise control's ability to maintain a steady speed, leading to inconsistent performance. Another potential issue is a defective speed sensor, which can provide inaccurate speed readings and cause the cruise control to malfunction. Problems with the throttle cable, such as it being stuck or damaged, can also hinder the system's operation. Lastly, electrical problems, including blown fuses or wiring issues, can significantly impact the cruise control functionality. By identifying and addressing these common problems, DIYers can effectively troubleshoot and resolve issues with the cruise control system in their vehicle.

How urgent is it to repair the non-functioning cruise control in a 2001 Mercedes-Benz ML320?

When it comes to the non-functioning cruise control in a 2001 Mercedes-Benz ML320, the urgency of repair is relatively low from a safety standpoint. This feature, while convenient for maintaining speed during long drives, does not directly affect critical vehicle functions such as braking or steering. However, neglecting to repair the cruise control can lead to inconveniences during extended trips, where the driver may find it tiring to manually maintain speed. While the malfunction does not pose an immediate risk, addressing it promptly can enhance your overall driving experience, making journeys more comfortable and enjoyable. Therefore, while it is not an urgent repair, taking the time to fix the cruise control can prevent future discomfort and ensure that you can fully enjoy the benefits of your vehicle's features.

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