P0559 Fault Code

Brake Booster Pressure Sensor Circuit Intermittent

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0559 fault code indicates an intermittent issue with the brake booster pressure sensor circuit. This sensor monitors the brake booster pressure, ensuring that adequate assistance is provided when braking. When this circuit experiences interruptions or failures, it can lead to compromised braking performance, which may pose safety risks.

What are the symptoms of the P0559 code?

Symptoms associated with a P0559 fault code may include:

• Illumination of the check engine light
• Decreased braking efficiency or responsiveness
• Erratic brake pedal feel
• Increased pedal effort required to engage brakes
• In some cases, the vehicle may enter 'limp' mode, restricting engine power to prevent further complications

What causes the P0559 code?

Common causes of a P0559 fault include:

• Faulty brake booster pressure sensor
• Damaged or corroded wiring or connectors in the circuit
• A vacuum leak in the brake system
• Malfunctioning brake booster
• Poor ground connections that affect the sensor's operation

How to fix P0559?

To resolve the P0559 fault code, consider the following:

• Inspect and replace the brake booster pressure sensor if faulty
• Check and repair any damaged wiring or connectors in the sensor circuit
• Ensure all ground connections are secure and free from corrosion
• Look for and repair any vacuum leaks in the brake system
• If needed, replace the brake booster if it is found to be malfunctioning