P0558
UniversalBrake Booster Pressure Sensor Circuit High Input
High SeverityThe P0558 code indicates that the vehicle's powertrain control module (PCM) has detected a high voltage input from the brake booster pressure sensor circuit. This typically means the sensor is sending a signal that is too high, suggesting a problem with the sensor itself, its wiring, or a vacuum issue with the brake booster system.
⚠️ Before You Begin (Safety First)
Always ensure the vehicle is safely supported on jack stands if working underneath. Disconnect the battery before performing any electrical work. Exercise extreme caution when working with brake system components, as compromised braking can lead to serious accidents. If braking performance feels significantly reduced, do not drive the vehicle.
Common Symptoms
- Illuminated Check Engine Light
- Hard brake pedal requiring more effort to stop
- Increased stopping distances
- Reduced brake assist
- Possibly ABS or Traction Control warning lights
Common Causes
- Faulty brake booster pressure sensor
- Open circuit or short to voltage in the sensor's wiring
- Corroded or loose electrical connectors
- Vacuum leak in the brake booster or associated vacuum lines
- Faulty Powertrain Control Module (PCM), though rare
Frequently reported on: Toyota Camry (2007-2011), Honda Civic (2006-2011), Ford F-150 (2004-2008), Chevrolet Silverado (2003-2007), Hyundai Sonata (2006-2010)
Diagnostic Steps
- Inspect the wiring harness and connectors for the brake booster pressure sensor for any signs of damage, corrosion, or loose connections. Repair as needed.
- Check all vacuum lines connected to the brake booster for cracks, leaks, or disconnections. Use a vacuum gauge to test the brake booster's vacuum integrity.
- Using a multimeter, test the brake booster pressure sensor's voltage output. Compare readings to manufacturer specifications.
- If the sensor is deemed faulty after testing, replace the brake booster pressure sensor.
- Clear the DTC (Diagnostic Trouble Code) and test drive the vehicle to ensure the code does not return and symptoms are resolved.
👨🔧 When to Call a Professional
If you experience a consistently hard brake pedal, significantly increased stopping distances, or if basic diagnostics (visual inspection, vacuum checks) do not reveal a clear fault, it is highly recommended to consult a professional mechanic. Brake system integrity is crucial for safety.
Commonly Asked Questions
What does P0558 mean for my car's braking?
P0558 indicates an issue with the brake booster's pressure sensor circuit, specifically a high voltage input. This can lead to a reduction in brake assist, making your brake pedal feel harder and requiring more effort to stop the vehicle.
Is it safe to drive with a P0558 code?
Driving with a P0558 code is generally not recommended, especially if you notice a significant decrease in braking performance. While the brakes will still work, the assist may be reduced, increasing stopping distances and creating a safety hazard.
Where is the brake booster pressure sensor located?
The brake booster pressure sensor is typically located on or near the brake booster, which is a large, round component usually mounted between the brake master cylinder and the firewall on the driver's side of the engine bay.
Can a vacuum leak cause P0558?
Yes, a vacuum leak in the brake booster or its associated lines can cause the P0558 code. A leak can affect the pressure readings, leading the sensor to report an incorrect high input to the PCM.
How expensive is it to fix a P0558 code?
The cost to fix P0558 varies. Replacing a faulty brake booster pressure sensor itself is generally inexpensive, ranging from $50-$150 for the part, plus labor. If the issue is a vacuum leak, it could be a simple hose replacement or a more costly brake booster replacement, which can range from $200-$600+ for parts and labor.