What Does P0558 Mean? OBD-II Code Powertrain Control Module (PCM) failure is defined as a Brake Booster Pressure Sensor Circuit High The Brake Booster uses vacuum to make the brake pedal easier to depress when braking. The Brake Booster Pressure Sensor measures the amount of vacuum inside the brake booster. If the engine computer sees an implausible signal from the Brake Booster Pressure Sensor, code P0558 will be set. engine code P0558P0558 fixobd P0558dtc P0558obd code P0558obd2 P0558P0558 car codediagnostic code P0558car code P0558check engine code P0558fehlercode P0558P0558 fiatcodigo P0558codigo falla P0558P0558 kody b??dówcodigo de falla P0558 What are the common causes of P0558 ? The most common cause of this code being stored is from vacuum leaks to the vacuum brake booster or a defective brake booster pressure sensor. Other causes may include shorted or open electrical circuitry and connectors, cracked or broken vacuum hoses to the brake booster, or a defective one way valve in the vacuum brake booster supply hose. Hydraulic brake boosters often fail due to power steering malfunctions, because the power steering pump also supplies hydraulic pressure to the booster. In this case, low power steering fluid is the most common culprit. A defective power steering pump may also cause low hydraulic brake booster pressure. How do you troubleshoot P0558 ? Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors. Look at the plug wires to make sure they are not burnt or laying on the exhaust. Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness. Searches related to P0558 Code - Brake Booster Pressure Sensor Circuit High Voltage p0558 p0557