P00FB: Turbocharger Outlet Pressure Sensor A Circuit High

The turbocharger outlet pressure sensor A measures the pressure directly after the compressor, usually ahead of the charge air cooler; FCA fits it as a combined temperature and pressure sensor. Boost control and compressor protection use the value. P00FB means the signal voltage is above its valid range: typically a signal wire shorted to the 5 V reference or battery voltage, an open ground, or a failed sensor. It does not mean the boost really is too high – that would be P0234. The circuit is monitored continuously from key-on; comparable GM pressure sensors fail above 86–97 % of the reference for about 4 s. The engine then works with a substitute value and may limit boost. GM and Ford do not use this code family in their published summaries – they rely on the boost sensor ahead of the throttle (P0235–P0238) – so no manufacturer document naming exactly this code was found.

Symptoms

• Check engine light on
• Loss of power or limp mode with boost limit
• Further pressure plausibility codes possible

Most likely causes

• Signal wire shorted to 5 V reference or battery voltage
• Ground (low reference) wire open or connector corroded
• Sensor faulty internally (oil mist, heat at compressor outlet)
• Engine control module faulty

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the hoses, clamps, and intercooler
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Compare commanded and actual pressure in live data
4. Check the actuator's movement
5. Check the vacuum hoses and the solenoid valve
6. Check the oil and the turbo shaft play before replacing it

Good to know

• Repair difficulty: easy
• It can trigger limp mode.
• It affects emissions.

What each character of P00FB means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 0: Subsystem depends on the code range
• FB: Specific fault in that system

Frequently asked questions

Can I keep driving with code P00FB?

Drive without demanding power and go to a repair shop soon. If you see a lot of blue smoke or hear a metallic noise, shut off the engine.

What causes code P00FB?

The most common causes are: signal wire shorted to 5 V reference or battery voltage; ground (low reference) wire open or connector corroded; sensor faulty internally (oil mist, heat at compressor outlet).

Related codes

• P00F8Turbocharger Outlet Pressure Sensor A Circuit
• P00F9Turbocharger Outlet Pressure Sensor A Range/Performance
• P00FATurbocharger Outlet Pressure Sensor A Circuit Low
• P00FCTurbocharger Outlet Pressure Sensor A Intermittent/Erratic
• P0238Turbocharger/Supercharger Boost Sensor A Circuit High
• P0234Turbocharger/Supercharger A Overboost Condition

Sources

• law.cornell.edu: 13 CCR 1968.2
• static.nhtsa.gov: MC 10220897 9999
• patents.google.com: US6298718
• gsi.ext.gm.com: 18OBDG03A Engine Diagnostics

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.