Turbocharger outlet pressure sensor A internally failed and is pulling the signal voltage high; A short to voltage in the signal wire between the sensor and the powertrain control module; Corroded, pushed-back or water-intruded terminals at the sensor connector or PCM connector; A chafed or pinched harness section where the signal wire rubs against a metal bracket or engine component; The sensor receiving an incorrect reference voltage because of a fault in the shared 5-volt reference circuit; A faulty powertrain control module, which is rare but possible after all circuit checks pass

DTC codes / P00xx · Fuel and air metering and auxiliary emission controls / P00FB

P00FBTurbocharger Outlet Pressure Sensor A Circuit High

Q: What does code P00FB mean?

Turbocharger Outlet Pressure Sensor A Circuit High. P00FB means the engine computer has detected an abnormally high voltage signal on the circuit for Turbocharger Outlet Pressure Sensor A, which is the sensor that measures boost pressure at the compressor outlet. The computer expects the signal voltage to stay within a calibrated range, and a sustained high reading tells it the circuit is shorted to voltage, the sensor has failed, or the reference voltage is being applied where it should not be.

P00FB means the engine computer has detected an abnormally high voltage signal on the circuit for Turbocharger Outlet Pressure Sensor A, which is the sensor that measures boost pressure at the compressor outlet. The computer expects the signal voltage to stay within a calibrated range, and a sustained high reading tells it the circuit is shorted to voltage, the sensor has failed, or the reference voltage is being applied where it should not be.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering and auxiliary emission controls

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Reduced engine power or a limp-home mode triggered by the powertrain control module
Poor throttle response and sluggish acceleration because boost pressure is being misreported
Rough running or hesitation under load if the faulty signal skews fuel and boost control
A boost-related message on the driver information display in some vehicles

Common causes, most likely first

Turbocharger outlet pressure sensor A internally failed and is pulling the signal voltage high
A short to voltage in the signal wire between the sensor and the powertrain control module
Corroded, pushed-back or water-intruded terminals at the sensor connector or PCM connector
A chafed or pinched harness section where the signal wire rubs against a metal bracket or engine component
The sensor receiving an incorrect reference voltage because of a fault in the shared 5-volt reference circuit
A faulty powertrain control module, which is rare but possible after all circuit checks pass

How to diagnose and fix it

Scan all modules and record freeze-frame data for P00FB before clearing anything, so you know the exact conditions when the fault set
Inspect the sensor connector and the harness run to the PCM for corrosion, pushed pins, chafing and signs of water intrusion
Back-probe the sensor signal wire with a digital multimeter and compare the key-on engine-off voltage against the manufacturer's expected range
Disconnect the sensor and check whether the signal wire still shows voltage with the sensor out of the circuit, which confirms a short to voltage in the harness
Check the shared 5-volt reference and sensor ground circuits at the sensor connector to rule out a reference fault that is skewing the signal
If the harness and reference circuits test good, substitute a known-good sensor and recheck live data before condemning the PCM
Clear the code after the repair and complete a drive cycle with boost applied to confirm the signal stays within range and the code does not return

What a high boost sensor signal really means

A high signal voltage does not automatically mean the sensor is bad, because a short to voltage anywhere on the signal wire will produce the same reading and replacing the sensor will not fix it.
Technicians often overlook the shared 5-volt reference circuit, so a fault there can skew the turbocharger outlet pressure signal and set P00FB along with codes for other sensors on the same reference.
Water intrusion and corrosion at the sensor connector are common on vehicles that see road spray or pressure-washing, and the terminals can look clean from the outside while the pins are green inside.
A failed sensor can read high while the engine is off and key-on, so comparing the key-on engine-off reading against barometric pressure is a quick way to spot a skewed sensor before chasing the harness.
P00FB can appear after an engine or turbocharger repair if the harness was pinched during reassembly, so always check recent work areas before assuming a component failure.

Can I keep driving with P00FB?

The vehicle is usually safe to drive to a repair shop, but avoid heavy throttle and towing because the computer may be limiting boost and misreporting pressure. If the engine goes into limp mode or runs poorly, keep the trip short and have it diagnosed promptly.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.