The 2018 Silverado is known for its power, reliability, and advanced systems like StabiliTrak and the trailer brake system, which provide extra safety and control while driving and towing. However, if you see the “Service StabiliTrak” and “Trailer Brake” messages appear on your dashboard, it can be alarming. These warnings indicate that the stability control and trailer brake systems are malfunctioning, potentially compromising your vehicle’s safety and towing ability. In this blog post, we’ll explore what these messages mean, common causes, and how to diagnose and fix these issues on your 2018 Silverado.
What is StabiliTrak?
StabiliTrak is GM’s stability control system designed to help you maintain control of your vehicle in slippery or uneven conditions. The system works by monitoring wheel speed and steering angle and applying braking to specific wheels to help keep the vehicle stable. If the system detects a loss of control, such as during a skid or a slide, it intervenes by reducing engine power or applying brakes to individual wheels to regain control.
The Service StabiliTrak message usually indicates that the system has been disabled due to a malfunction, which can compromise vehicle safety.
What is the Trailer Brake System?
The trailer brake system controls the braking force applied to your trailer, ensuring that both your truck and trailer slow down evenly. When the trailer brake system isn’t working properly, you’ll see the “Trailer Brake System” warning message. This system is essential for safe towing, particularly when hauling heavy loads.
If you receive both the Service StabiliTrak and Trailer Brake System warnings simultaneously, it’s important to diagnose and repair these issues immediately.
Common Causes of StabiliTrak and Trailer Brake System Warnings
The following are some of the most common reasons why you might see the Service StabiliTrak and Trailer Brake System messages on your 2018 Silverado:
- Faulty Wheel Speed Sensors
One of the key components of the StabiliTrak system is the wheel speed sensor. If one of these sensors fails or becomes dirty, the system can’t accurately monitor the speed of the wheels, causing the Service StabiliTrak warning to appear. - Brake Switch Malfunction
The brake switch tells the vehicle when you’re pressing the brake pedal. A faulty brake switch can cause issues with both the StabiliTrak and trailer brake systems, leading to simultaneous warnings. - Trailer Wiring Issues
A damaged or corroded trailer wiring harness can interrupt the communication between your truck and trailer, causing the Trailer Brake System message. Additionally, wiring issues can affect the StabiliTrak system if the vehicle perceives erratic data due to poor electrical connections. - Blown Fuses
Both the StabiliTrak and trailer brake systems rely on the truck’s electrical system. A blown fuse could cut power to these systems, triggering the warning messages. - Low Brake Fluid
The StabiliTrak system relies on the vehicle’s braking system to function correctly. If your brake fluid level is low, it can cause the Service StabiliTrak message to appear. - Software Issues
Occasionally, the problem may be a software glitch in the vehicle’s onboard computer. This could cause the systems to behave erratically and display false warnings.
How to Diagnose and Fix Service StabiliTrak and Trailer Brake Issues
Addressing the Service StabiliTrak and Trailer Brake System warnings requires a systematic approach. Follow these steps to diagnose and fix the issues:
Step 1: Check the Brake Fluid Level
Begin by checking the brake fluid level in your 2018 Silverado. Low brake fluid can cause both the StabiliTrak and trailer brake systems to malfunction. Here’s how to check the brake fluid:
- Locate the Brake Fluid Reservoir: It’s usually found near the back of the engine compartment, close to the windshield on the driver’s side.
- Check the Fluid Level: Ensure that the brake fluid level is between the minimum and maximum marks on the reservoir. If it’s low, top it up with the recommended brake fluid for your vehicle.
- Inspect for Leaks: If your brake fluid is low, inspect the brake lines and calipers for signs of leaks. Leaking brake fluid can lead to serious issues with both braking and stability control.
Step 2: Inspect the Wheel Speed Sensors
If your brake fluid is at the correct level, the next step is to inspect the wheel speed sensors. These sensors are located near the wheels and monitor each wheel’s speed to help the StabiliTrak system function properly.
- Visually Inspect the Sensors: Look for any signs of damage or dirt on the sensors. Clean any debris away from the sensors with a soft brush or cloth.
- Test the Sensors: Use a multimeter to test the sensors for continuity. If one of the sensors is faulty, you’ll need to replace it to restore the StabiliTrak system.
Step 3: Check the Trailer Wiring
If the Trailer Brake System warning is present, inspect the trailer wiring for any damage or corrosion:
- Inspect the 7-Pin Connector: Ensure that the 7-pin connector between the truck and trailer is clean, secure, and free from corrosion. Use electrical cleaner to clean the contacts if necessary.
- Check the Wiring Harness: Follow the wiring from the connector to the trailer brake components. Look for any frayed wires, damaged insulation, or loose connections that could be causing the system to malfunction.
Step 4: Test the Brake Switch
The brake switch is responsible for communicating when you press the brake pedal. A malfunctioning switch can trigger both the StabiliTrak and trailer brake system warnings.
- Test the Brake Switch: Depress the brake pedal and observe whether the brake lights illuminate. If the brake lights don’t come on, the switch may be faulty and need to be replaced.
Step 5: Check the Fuses
If you’ve ruled out fluid levels, sensors, and wiring, the issue could be related to a blown fuse. Check the vehicle’s fuse box for any blown fuses related to the StabiliTrak or trailer brake system:
- Locate the Fuse Box: The fuse box is usually located under the hood on the driver’s side. Consult your owner’s manual for the exact location and layout of the fuses.
- Inspect the Fuses: Look for any blown fuses that correspond to the StabiliTrak and trailer brake systems. Replace any blown fuses with new ones of the same amperage.
Step 6: Perform a System Reset
If you’ve addressed the issues above but the warning messages remain, try resetting the system. Disconnect the truck’s battery for a few minutes to clear any stored error codes in the onboard computer. After reconnecting the battery, start the truck and see if the warnings have cleared.
Preventative Maintenance Tips
To avoid future StabiliTrak and trailer brake system issues, follow these preventative maintenance tips:
- Regularly Inspect Wiring: Check the trailer wiring before each trip to ensure there are no loose or damaged connections. This will help prevent communication issues between the truck and trailer.
- Service the Brake System Annually: Have the brakes serviced annually to ensure the system is working correctly. This includes checking fluid levels, replacing worn-out brake components, and testing the brake switch.
- Keep Wheel Speed Sensors Clean: Clean the wheel speed sensors regularly to prevent debris from interfering with the StabiliTrak system.
Conclusion
When your 2018 Silverado displays the Service StabiliTrak and Trailer Brake System warnings, it’s essential to diagnose and fix the problem promptly. By following the steps outlined in this guide, you can address the common causes of these warnings and ensure that both your stability control and trailer brake systems are functioning correctly. Regular maintenance and timely repairs will keep your Silverado safe and reliable on the road, whether you’re driving in adverse conditions or towing a trailer.