P0391 Camshaft Position Sensor B Circuit Range Performance Bank 2

Definition: The P0391 code indicates that the Engine Control Module (ECM) has detected a problem with the camshaft position sensor B circuit in bank 2. This could mean that the signal from the sensor is not within the expected range or performance parameters.

p0391 camshaft position sensor b circuit range performance bank 2: Moderate

Common Causes

P0391 – Camshaft Position Sensor “B” Circuit Range/Performance Bank 2

• Incorrect camshaft timing
• Faulty camshaft position sensor
• Wiring issues (short circuit, open circuit)
• Connector problems (loose or corroded connections)
• Engine mechanical problems (timing chain/belt issues)

 

Common Misdiagnosis

OBD2 Code: P0391

Description: Camshaft Position Sensor B Circuit Range/Performance (Bank 2)

Common Misdiagnosis: Replacing the camshaft position sensor without checking for wiring issues or problems with the timing chain/belt.

 

Common Diagnostic Steps

OBD2 Code: P0391

Description: Camshaft Position Sensor B Circuit Range/Performance Bank 2

• Check for any additional trouble codes that may be present, as they can provide more context to the issue.
• Inspect the camshaft position sensor and its wiring for damage or disconnection. Ensure all connectors are secure.
• Test the camshaft position sensor using a multimeter to ensure it is functioning within specifications.
• Examine the timing chain or belt for proper alignment and tension, as misalignment can affect sensor readings.
• Verify that there is no oil contamination on the sensor or connector, which could interfere with signal transmission.
• If applicable, check for any updates or technical service bulletins (TSBs) related to this code from the vehicle manufacturer.
• If necessary, replace the camshaft position sensor with a new one and clear the code to see if it returns.