HomeTrouble CodesP2377

P2377 — Turbochargersupercharger Inlet Pressure Sensor B Circuit High

Manufacturer-specificPowertrain (engine & transmission)

P2377 means the engine control module has detected a voltage signal from the turbocharger/supercharger inlet pressure sensor B that is higher than the expected range. This sensor measures pressure at the compressor inlet; a high circuit reading usually indicates a fault with the sensor, its wiring, or a rare ECM input issue.

Symptoms

What causes it — most likely first

1. Faulty inlet pressure sensor B

The sensor itself may have an internal short or failure causing its output voltage to read excessively high.

2. Wiring harness short to voltage or power

Damage to the signal wire (e.g., chafing, melted insulation) can cause it to contact a 12 V source, pulling the signal high.

3. Corroded or loose connector at sensor B or ECM

Poor contact can create a false high voltage reading due to increased resistance or intermittent power coupling.

4. ECM/PCM input circuit fault

A rare internal fault in the ECM’s sensor input circuit can register a high voltage even with a good sensor and wiring.

How it's diagnosed

  1. Scan for codes and record freeze‑frame data to confirm P2377 is present
  2. Visually inspect the inlet pressure sensor B, its connector, and wiring for damage, corrosion, or loose connections
  3. Measure sensor supply voltage and ground at the connector with a multimeter; verify they are within manufacturer specifications
  4. Check sensor signal voltage while the engine is running; compare to expected pressure‑to‑voltage curve
  5. Perform a continuity and short‑to‑power test on the sensor signal wire between the sensor and ECM
  6. If wiring and connector are good, substitute a known‑good sensor B to see if the code clears

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Is it common to replace the PCM/ECM for P2377?

No. The PCM/ECM is seldom the cause; most cases are due to the sensor, its wiring, or connector. Replacing the module should only be considered after all sensor and wiring checks have been completed and the code persists.

Can I continue driving with this code active?

Driving is possible but not recommended for extended periods. The ECM may limit boost or power, and an incorrect pressure reading could lead to overboost or engine damage if the condition worsens.

Will cleaning the sensor fix the problem?

Cleaning the sensor exterior will not resolve an internal electrical fault or wiring issue. If the sensor is contaminated, cleaning may help, but a high circuit voltage usually points to an electrical fault rather than dirt.

After fixing the cause, do I need to clear the code manually?

Yes. After the repair, clear the code with a scan tool and verify that it does not return during a test drive.