Description of the P0573 fault code.
OBD2 Error Codes

P0573 Cruise control/brake switch “A” circuit high

26.05.2022 /

P0573 – OBD-II Trouble Code Technical Description

Trouble code P0573 indicates that the PCM has detected a high signal level in the cruise control/brake switch “A” circuit.

What does the fault code mean P0573?

Trouble code P0573 indicates an electrical problem in the brake pedal switch “A” circuit, which is part of the vehicle's cruise control system. This code means that the engine control module (PCM) has detected abnormal resistance or voltage in this circuit. If the PCM receives a signal that the vehicle can no longer control its own speed, it will begin testing the entire cruise control system. The P0573 code will appear if the vehicle's PCM detects that the resistance and/or voltage in the brake pedal switch circuit is abnormal. This means that the car cannot control its own speed and therefore the cruise control must be turned off.

Fault code P0573.

Possible reasons

Some of the possible causes of the P0573 trouble code are:

  • Brake pedal switch is damaged or worn: Mechanical damage or wear to the brake pedal switch may cause abnormal resistance or voltage in the circuit.
  • The wiring in the brake switch circuit is open or shorted.: The wiring connecting the brake pedal switch to the PCM may be open or shorted, causing abnormal resistance or voltage readings.
  • Problems with PCM: Faults or damage in the PCM may cause the brake pedal switch to not read correctly.
  • Problems with the car's electrical system: Insufficient power or insufficient grounding of the brake pedal switch or PCM can cause abnormal resistance or voltage in its circuit.
  • Problems with cruise control: Some cruise control problems can cause a P0573 code to appear because the brake pedal switch is used to activate and deactivate it.

To accurately determine the cause, it is recommended to carry out additional diagnostics of the vehicle using specialized equipment or contact a certified auto mechanic.

What are the symptoms of a fault code? P0573?

Some possible symptoms when trouble code P0573 appears:

  • Disabling cruise control: One of the main symptoms is the cruise control turning off. Since the brake pedal switch is used to activate and deactivate the cruise control, a fault in its circuit may cause the cruise control to automatically disengage.
  • Brake light malfunction: In some cases, the brake pedal switch is also responsible for activating the brake lights. If it is not functioning correctly due to a malfunction, the brake lights may not work properly or at all.
  • Check Engine Light: Typically, when a P0573 trouble code is detected, the Check Engine Light or other warning lights may illuminate on your dashboard.
  • Gear shifting problems: On some vehicles, the brake pedal switch may also be linked to the shift lock. Therefore, problems with this switch may make it difficult or impossible to shift gears.

If you experience these symptoms, it is recommended that you immediately contact a qualified auto mechanic to diagnose and repair the problem.

How to diagnose a fault code P0573?

The following steps are recommended to diagnose DTC P0573:

  1. Check the brake pedal switch: Check the brake pedal switch for visible damage or wear. Make sure it is securely fastened and free of corrosion.
  2. Check electrical connections: Check all electrical connections in the brake pedal switch circuit for corrosion, blown fuses, or broken wiring. Make sure all connections are tight and show no signs of damage.
  3. Use a trouble code scanner: Use a trouble code scanner to read other codes that may be related to this problem, as well as to check the current brake pedal switch settings.
  4. Check the operation of the cruise control: Check the operation of the cruise control to ensure that it activates and deactivates correctly when you press the brake pedal.
  5. Check PCM: If all other tests do not reveal the problem, the PCM may need to be diagnosed using specialized vehicle equipment.
  6. Check wires and connectors: Check the wires and connectors from the brake pedal switch to the PCM for breaks, corrosion, or other damage.

If you cannot independently identify the cause of the malfunction, it is recommended to contact a qualified auto mechanic or car service center for further diagnostics and repairs.

Diagnostic errors

When diagnosing DTC P0573, the following errors may occur:

  • Skipping brake pedal switch test: One error may be incorrect or incomplete testing of the brake pedal switch. Insufficient testing of this component may result in the problem being incorrectly detected.
  • Ignoring other fault codes: Sometimes the P0573 code can be associated with other trouble codes or problems in the cruise control system. Ignoring other codes or symptoms may result in an incomplete diagnosis and incorrect repairs.
  • Faulty wiring or connections: The error may occur due to incorrect diagnosis of wiring or electrical connections. Insufficient checking for breaks, corrosion or overheating may lead to incorrect identification of the cause.
  • Malfunctioning PCM: Sometimes a misdiagnosis may indicate a faulty PCM, although the cause may be related to other components. Replacing the PCM without proper diagnostics may be unnecessary and ineffective.
  • Improper repair: Attempting repairs without proper diagnosis may result in replacing unnecessary components or incorrect repairs that do not address the root cause of the problem.

To successfully diagnose and repair the P0573 code, you must carefully check all possible causes and conduct a comprehensive diagnosis.

How serious is the fault code? P0573?

Trouble code P0573 indicating a problem with the brake pedal switch in the vehicle's cruise control system can be serious, especially to the safety and drivability of the vehicle, there are several aspects that make this code serious:

  • Potential disabling of cruise control: Since the brake pedal switch is used to activate and deactivate cruise control, malfunction of the brake pedal switch may prevent the vehicle from being able to control the speed of the vehicle using cruise control. This can be especially problematic on long highway trips.
  • Potential Security Issues: The brake pedal switch also activates the brake lights when the brakes are applied. If it is not functioning properly, it can create a hazard for other road users as other drivers may not notice that you are braking.
  • Driving restrictions: Some vehicles use a brake pedal switch to lock the gear shift. A malfunction of this switch can cause problems with shifting gears, which can be dangerous when driving.

Given these factors, code P0573 should be considered a serious problem that requires prompt attention and resolution.

What repair will help eliminate the code? P0573?

Resolving trouble code P0573 requires careful diagnosis and possible repair or replacement of cruise control system components. A few steps that can help resolve this issue:

  1. Checking and replacing the brake pedal switch: First check the brake pedal switch for any problems. If it is damaged or does not function properly, it should be replaced.
  2. Checking electrical connections: Carry out a thorough check of the electrical connections in the brake pedal switch circuit. Make sure all wires are intact and free of corrosion and tight connections.
  3. PCM diagnostics: If the problem is not with the brake pedal switch or electrical connections, it may be due to a faulty PCM. In this case, diagnostics will be required and the PCM may need to be replaced or reprogrammed.
  4. Checking other cruise control components: Sometimes a P0573 code can be caused by a problem with other components of the cruise control system, such as the cruise control actuator or the wiring to it. Check these components for faults.
  5. Additional checks: Additional checks may need to be performed depending on specific circumstances. This may include checking fuses, relays or other system components.

After a thorough diagnosis and determination of the root cause of the problem, the necessary repairs or replacement of components should be performed. If you do not have sufficient skills or experience to repair your vehicle, it is recommended that you contact a qualified auto mechanic or auto repair shop.

GM P0573 Troubleshooting Tips You Need To Know!

P0573 – Brand-specific information

Trouble code P0573 can occur on various brands of cars, a list of some brands with explanations:

These are just some of the possible interpretations of the P0573 code for various makes of vehicles. For your specific vehicle make and model, it is always best to consult the manufacturer's documentation or service manual

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