p0557 brake booster pressure sensor circuit low
P0557 Brake Booster Pressure Sensor Circuit Low
Definition: This code indicates that the vehicle’s powertrain control module (PCM) has detected a low voltage signal from the brake booster pressure sensor circuit, which is below the expected range.
P0557 – Brake Booster Pressure Sensor Circuit Low
Typical Severity: Moderate
Common Causes
P0557 – Brake Booster Pressure Sensor Circuit Low
Description: The Powertrain Control Module (PCM) has detected a low voltage signal from the brake booster pressure sensor circuit.
Common Causes:
- Faulty brake booster pressure sensor
- Corroded or damaged wiring in the brake booster pressure sensor circuit
- Poor electrical connection at the brake booster pressure sensor
- Low brake fluid level
- Faulty PCM
Common Misdiagnosis
OBD2 Code: P0557
Description: Brake Booster Pressure Sensor Circuit Low
Common Misdiagnosis: Replacing the brake booster pressure sensor without checking for wiring issues or vacuum leaks.
Common Diagnostic Steps
OBD2 Code: P0557
Description: Brake Booster Pressure Sensor Circuit Low
- Check for any stored trouble codes and freeze frame data using an OBD2 scanner.
- Inspect the brake booster pressure sensor and its wiring for damage or disconnection.
- Test the voltage at the brake booster pressure sensor connector with a multimeter to ensure it is within specifications.
- Examine the vacuum lines connected to the brake booster for leaks or blockages.
- Verify that the vehicle’s battery and charging system are functioning properly, as low voltage can affect sensor performance.
- If all checks pass, consider replacing the brake booster pressure sensor if it is suspected to be faulty.