Cruise Control/Brake Switch A Circuit Low
The P0572 code indicates that the powertrain control module (PCM) has detected a low voltage signal from the brake switch A circuit. This switch is typically used to disengage the cruise control when the brake pedal is pressed. A low voltage condition may be caused by a faulty brake switch, a short to ground in the wiring, or a problem with the PCM. This can prevent the cruise control from working properly and may also affect brake light operation.
1. Most Common Causes
- Faulty brake switch
- Short to ground in brake switch circuit
- Corroded or damaged wiring/connectors
- Failed PCM (rare)
2. Symptoms You Will Notice
- Cruise control inoperative
- Brake lights may not work or stay on constantly
- Check Engine Light illuminated
- Possible ABS or traction control warning lights
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify the code and check for additional codes.
Step 2: Inspect the brake switch and its wiring for damage, corrosion, or loose connections.
Step 3: Test the brake switch operation using a multimeter; check for proper voltage and continuity.
Step 4: If the switch and wiring are okay, test the circuit at the PCM connector to rule out a PCM issue.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally safe to drive, but the cruise control will not work and brake lights may malfunction, which could be a safety concern. It is recommended to diagnose and repair promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150, including parts (brake switch) and labor. Diagnostic fees may apply.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.