Booster Pressure Sensor Fault
The system has detected a malfunction in the booster pressure sensor.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The booster pressure sensor monitors the pressure in the brake booster system. If it sends the wrong pressure reading or fails, the engine may not have the correct braking assist, leading to harder braking and potential safety issues.
What the computer is actually seeing
The engine control module (ECM) expects a pressure reading from the booster pressure sensor to be between 0.5 to 5.0 volts, corresponding to a pressure range of approximately 5 to 30 psi. If the voltage is out of this range or the sensor is unresponsive, a fault code is triggered.
What a healthy reading looks like
Expected voltage is 0.5 to 5.0 volts for a pressure range of 5 to 30 psi.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring and connector at the booster pressure sensor for any damage or corrosion. Repair if needed. Decision: If there's a wiring issue, fix it and clear the code; if not, proceed to step 2.
- 22. Measure the voltage at the booster pressure sensor connector with the key on, engine off. Expect 0.5 to 5.0 volts. Decision: If you get the correct voltage, the sensor may be good; if not, proceed to step 3.
- 33. With the engine running, observe the voltage while pressing the brake pedal. It should vary smoothly with pressure. Decision: If the voltage does not change, replace the sensor; if it does, check the brake booster system and ECM.
Common causes
- Faulty booster pressure sensor
- Wiring issues (shorts or opens)
- Corroded or damaged connectors
- Brake booster malfunction
- ECM issues
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this fault code?
Not recommended. The brake system may not function properly, affecting safety.
Will this code come back after clearing it?
If the underlying issue isn't fixed, it will likely return.
Why does this code pair with other SPN codes?
These codes often relate to related systems, like the brake booster or other pressure sensors.
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