Introduction to the P0573 Trouble Code in Chevy Silverado
The modern Chevrolet Silverado is equipped with advanced automotive technology, including the state-of-the-art Adaptive Cruise Control (ACC) system. This intelligent system adjusts the vehicle’s speed automatically based on the surrounding traffic conditions, enhancing driving comfort and safety. However, like all complex electronic systems, it can occasionally trigger diagnostic trouble codes (DTCs) that indicate underlying issues.
One such code is the P0573, which signals a malfunction within the cruise control or brake switch circuitry. Understanding this code is essential for diagnosing and resolving potential safety and performance problems associated with your Silverado.
What Does the P0573 Code Mean on Chevy Silverado?
The P0573 code is a generic Car Computer Diagnostic trouble code that indicates the vehicle’s Powertrain Control Module (PCM) has detected an abnormal voltage signal in the cruise control/brake switch circuit. Specifically, it points to a high voltage condition in the ‘A’ circuit of the ACC brake switch—a critical component responsible for communicating brake pedal engagement to the vehicle’s electronic control units.
This high voltage reading can result from electrical anomalies such as wiring issues, a faulty brake switch, or problems within the PCM itself. When triggered, this code often causes the cruise control system to disable or function erratically, which can impact driving comfort and safety.
Understanding the Role of the Brake Switch in Chevy Silverado
The brake switch, often called the Stop/Brake light switch, plays a pivotal role in vehicle operation. It sends signals to the PCM indicating when the brake pedal is pressed, thereby disengaging cruise control and activating brake lights. This switch is mounted near the brake pedal arm and is designed to detect pedal position accurately.
If this switch malfunctions—due to electrical wear, misalignment, or debris—it can send incorrect signals or high voltage spikes to the PCM, resulting in the P0573 trouble code. Proper functioning of this switch is vital for vehicle safety features and cruise control operation.
Implications of the P0573 Code Activation
When the PCM detects an abnormal high voltage in the cruise control/brake switch circuit, it interprets this as a fault. Consequently, the vehicle’s cruise control system may automatically disengage, or the system may refuse to activate altogether. Additionally, warning lights such as the Check Engine indicator may illuminate on the dashboard.
This behavior ensures driver safety by preventing the cruise control system from operating under faulty conditions. However, it also signals that immediate diagnosis and repair are necessary to restore normal vehicle functions.
Common Causes Behind the P0573 Error
- Electrical short circuits or open circuits within the cruise control or brake switch wiring harness.
- A defective or worn brake pedal switch that sends inconsistent signals.
- Damaged or malfunctioning PCM or ECM components.
- Incorrect switch adjustment or misalignment, causing the switch to send erroneous signals.
- Blown fuses related to the cruise control or brake light circuits.
>Corrosion or debris obstructing the switch or its connectors.
Symptoms Associated with the P0573 Code
- The cruise control system fails to engage or disengages unexpectedly.
- Brake lights may not illuminate when the brake pedal is pressed.
- Warning lights, such as the Check Engine light, are illuminated on the dashboard.
- Intermittent or non-functioning cruise control behavior.
- Potential difficulty in maintaining vehicle speed at the set level.
Diagnosing and Fixing the P0573 Issue
Addressing the P0573 code involves a systematic approach, starting with visual inspections and electrical testing:
Tools Needed:
- Digital multimeter
- Screwdrivers (Phillips and flat-head)
- Socket wrench set
- Replacement brake switch (if necessary)
Step-by-Step Repair Procedure:
1. Disconnect the Battery
Begin by turning off the ignition, removing the key, and disconnecting the negative terminal of the battery to prevent electrical shorts and ensure safety during repairs.
2. Access the Brake Switch
Locate the brake pedal assembly inside the vehicle. The brake switch is usually mounted on or near the brake pedal arm. Carefully remove any panels or coverings to gain access.
3. Inspect the Wiring and Connectors
Check for corrosion, damaged wires, or loose connections. Use a multimeter to test for proper voltage levels and continuity across the switch.
4. Test or Replace the Brake Switch
If testing indicates a faulty switch, replace it with a new, OEM-quality part. Reconnect all wiring securely.
5. Reassemble and Test
Reinstall any panels, reconnect the battery, and start the vehicle. Verify if the cruise control system functions correctly and if the error code has been cleared.
Estimated Repair Costs
The overall expense depends on whether you perform the repair yourself or seek professional help:
| Part Replacement Cost | $20 – $55 |
| Labor Charges (if using a mechanic) | $75 – $150 per hour |
DIY repairs can minimize costs, but professional diagnostics are recommended for complex electrical issues.
Frequently Asked Questions (FAQs)
Where exactly is the brake/stop light switch located in a Chevy Silverado?
The brake switch is mounted on the brake pedal assembly, typically near the pivot point, and connected to the brake pedal arm. It is accessible from beneath the dashboard or through the footwell.
Are the brake light switch circuit and cruise control circuit the same?
While interconnected, they are distinct circuits. The brake light switch primarily controls the brake lights, whereas the cruise control circuit communicates pedal engagement to the PCM. However, electrical faults can affect both.
Is replacing the brake light switch an expensive repair?
Generally, it is an affordable and straightforward replacement, costing between $20 and $55 for parts, plus minimal labor if done professionally.
Can issues with vacuum hoses or actuators trigger the P0573 code?
While vacuum-related components are less directly involved, any electrical or sensor malfunction affecting the brake switch signal can contribute to this code.
Final Thoughts
The P0573 code in your Chevy Silverado indicates a high voltage issue within the cruise control or brake switch circuit, often caused by electrical faults or switch malfunctions. Addressing this promptly ensures safe vehicle operation and restores the cruise control functionality. Whether you choose a DIY repair or professional service, understanding the underlying causes helps in making informed decisions and maintaining your vehicle’s optimal performance.