2008 Mercedes-Benz SL550 Cruise Control Isn't Working

Fixing Cruise Control Issues in 2008 Mercedes-Benz SL550

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 2008 Mercedes-Benz SL550 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 2008 Mercedes-Benz SL550 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.

What are the steps to diagnose the cruise control issue in a 2008 Mercedes-Benz SL550?

To effectively diagnose a cruise control issue in your 2008 Mercedes-Benz SL550, begin with the simplest checks to avoid unnecessary complications. Start by inspecting the cruise control fuse; a blown fuse is a common culprit that can easily disrupt functionality. Next, examine the cruise control switch located on the steering wheel, as a malfunctioning switch can prevent the system from engaging. If these initial checks do not resolve the issue, utilize a diagnostic scanner to identify any error codes from the vehicle's onboard computer, which can provide insights into specific problems. Following this, assess the speed sensors, as they are vital for the cruise control system's operation; faulty sensors can hinder the system's ability to maintain speed. Additionally, inspect the wiring and connections associated with the cruise control system for any signs of damage or corrosion, as these can impede proper function. Finally, if all else fails, test the cruise control module to ensure it is communicating effectively. By systematically following these steps, you can diagnose and potentially resolve cruise control issues, restoring your vehicle's functionality with confidence.

What are the common problems that could cause the cruise control to stop working in a 2008 Mercedes-Benz SL550?

When the cruise control in your 2008 Mercedes-Benz SL550 ceases to function, it can be frustrating, but understanding the common problems can help you diagnose the issue effectively. One of the first components to check is the brake pedal switch, as a defective switch can interrupt the cruise control system's operation. Additionally, a blown fuse related to the cruise control system may also be the culprit, so inspecting the fuse box for any damaged fuses is essential. Another area to consider is the brake lights; if they are not functioning correctly due to a faulty brake light or switch, this can prevent the cruise control from engaging. Furthermore, ensure that your vehicle's battery is in good condition, as a dead battery can lead to various electrical issues, including problems with cruise control. Lastly, a malfunctioning ABS wheel speed sensor can also disrupt the cruise control system, so checking this sensor is advisable. By systematically examining these components, you can identify and resolve the issue, restoring your cruise control functionality.

How urgent is it to address the malfunctioning cruise control in a 2008 Mercedes-Benz SL550?

Addressing the malfunctioning cruise control in a 2008 Mercedes-Benz SL550 is of utmost urgency due to the significant safety risks it poses. A malfunction can lead to unexpected acceleration or deceleration, which can endanger both the driver and other road users. Additionally, a faulty cruise control system detracts from the overall driving experience, making it inconvenient and frustrating to operate the vehicle. Ignoring these symptoms not only compromises safety but can also lead to further damage within the vehicle's systems, resulting in more extensive and costly repairs down the line. Therefore, it is crucial for owners to prioritize the diagnosis and repair of cruise control issues to ensure a safe and enjoyable driving experience while protecting their investment in the 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.

2008 Mercedes-Benz SL550 Cruise Control Malfunction Guide