P0238 OBD-II Trouble Code: Turbocharger Boost Sensor A Circuit High

P0238 code definition

Turbocharger Boost Sensor A Circuit High

What the P0238 code means

P0238 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost pressure sensor A input circuit out of specifications, indicating an open circuit or high voltage condition in the circuit.

What causes the P0238 code?

• Turbo boost pressure sensor internally open circuit

• The turbo boost pressure sensor A connector is damaged, causing an open circuit

• The turbo boost pressure sensor A wiring is shorted to power between the sensor and the ECM

What are the symptoms of the P0238 code?

• The Check Engine Light will be illuminated and code set

• The engine turbo boost may be turned off by the ECM and the engine will lack power (during acceleration)

How does a mechanic diagnose the P0238 code?

• Scans codes and documents the freeze frame data in order to verify the problem

• Clears the codes to verify whether the concern comes back

• Checks the operation of the boost pressure sensor signal and compares it to the MAP sensor at engine idle to see if the readings are the same

• Checks the turbo boost sensor wiring and connector for any signs of shorts to power in the harness

• Checks the turbo boost sensor connector for corroded pins that may cause shorting of power in the signal circuit

• Compares readings to specifications on the sensor data scan

Common mistakes when diagnosing the P0238 code?

Follow these simple guidelines to prevent misdiagnosis:

• Try disconnecting the sensor to see if the short to power and code goes away or changes

• Check the harness for melting from loose or hanging wire looms on the exhaust

How serious is the P0238 code?

• A short to a power source in the sensor circuit can cause the ECM to get internally burned out if the circuit short goes over 5 volts.

• If the ECM gets burned out, then the vehicle may stall and not start.

What repairs can fix the P0238 code?

• Replacing the boost sensor if it is shorted internally and not giving the correct input pressure reading to the ECM

• Repairing the wiring harness if any shorts are found, and securing the harness from getting damaged

• Replacing the broken connectors causing the shorted or open circuits

• Replacing the ECM if it got shorted internally, and repairing the cause of the short

Additional comments for consideration regarding the P0238 code

Code P0238 is triggered when the intake boost sensor circuit shorts to power or opens completely, causing the signal to the ECM to go way over, or below voltage specifications. The most common failure is the boost sensor shorted internally, or the harness has been shorted on the exhaust manifold.

Need help with a P0238 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.