Faulty bypass valve solenoid or actuator on bank B; Damaged or disconnected electrical connector at the bypass valve; Open or shorted wiring in the control circuit between the PCM and the valve; Failed powertrain control module driver for the bypass valve circuit; Sticking or mechanically binding bypass valve assembly; Corroded or chafed wires due to heat or vibration near the turbocharger

DTC codes / P00xx · Fuel and air metering and auxiliary emission controls / P00C0

P00C0Turbocharger/Supercharger Bypass Valve B Control Circuit

Q: What does code P00C0 mean?

Turbocharger/Supercharger Bypass Valve B Control Circuit. P00C0 indicates that the powertrain control module has detected a fault in the control circuit for the bypass valve on the secondary turbocharger or supercharger, designated as bank B. The computer monitors the electrical circuit that commands the valve to open or close and sets this code when the expected voltage or current feedback does not match the commanded state.

P00C0 indicates that the powertrain control module has detected a fault in the control circuit for the bypass valve on the secondary turbocharger or supercharger, designated as bank B. The computer monitors the electrical circuit that commands the valve to open or close and sets this code when the expected voltage or current feedback does not match the commanded state.

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 under heavy acceleration
Poor throttle response or hesitation when the turbocharger or supercharger should engage
Audible hissing or whistling from the engine bay during acceleration or deceleration
Rough idle or stalling in some cases if the valve sticks open
Decreased fuel economy due to incorrect boost pressure management

Common causes, most likely first

Faulty bypass valve solenoid or actuator on bank B
Damaged or disconnected electrical connector at the bypass valve
Open or shorted wiring in the control circuit between the PCM and the valve
Failed powertrain control module driver for the bypass valve circuit
Sticking or mechanically binding bypass valve assembly
Corroded or chafed wires due to heat or vibration near the turbocharger

How to diagnose and fix it

Perform a visual inspection of the bypass valve, its connector, and the wiring harness for obvious damage or disconnection
Use a scan tool to command the bypass valve open and closed while watching live data to confirm the circuit responds
Measure resistance and voltage at the bypass valve connector to check for open or short circuits
Check for continuity and voltage drop across the control circuit wiring from the PCM to the valve
Test the bypass valve solenoid with a known-good actuator or apply direct power to verify operation
If the circuit and valve test good, diagnose the PCM driver or replace the PCM as a last resort
Clear the code and perform a road test to verify the repair and ensure the code does not return

Bypass valve circuit faults often misdiagnosed

A sticking mechanical bypass valve can set this code even when all electrical tests pass, so always verify free movement of the valve.
Heat damage to the connector or wiring near the turbocharger is a common cause that is easily overlooked during a quick visual inspection.
The code can be set by a momentary glitch in the circuit, so intermittent faults may require wiggle testing and data logging during a road test.
Replacing the bypass valve without checking the control circuit first often leads to a repeat failure and unnecessary expense.
On some vehicles, a low or weak battery can cause false circuit codes, so verify battery condition and charging system operation before condemning the valve.

Can I keep driving with P00C0?

The vehicle is generally safe to drive with this code, but avoid aggressive acceleration and heavy load until the fault is repaired, as incorrect boost control can lead to reduced performance or further damage to the turbocharger system.

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.