P0377 Timing Reference High Resolution Signal B Too Few Pulses

Definition: This diagnostic trouble code (DTC) indicates that the engine control module (ECM) has detected an insufficient number of pulses from the high-resolution timing reference signal B. This can affect the engine’s performance and efficiency.

p0377 – Timing Reference High Resolution Signal B Too Few Pulses

Typical Severity: Moderate

Common Causes

P0377 – Timing Reference High Resolution Signal B Too Few Pulses

Common Causes:

• Faulty crankshaft position sensor
• Wiring issues in the crankshaft position sensor circuit
• Engine timing out of adjustment
• Faulty engine control module (ECM)

 

Common Misdiagnosis

OBD2 Code: P0377

Description: Timing Reference High Resolution Signal B Too Few Pulses

Common Misdiagnosis: Replacing the crankshaft position sensor without checking for wiring issues or problems with the reluctor wheel.

 

Common Diagnostic Steps

OBD2 Code: P0377

Description: Timing Reference High Resolution Signal B Too Few Pulses

Common Diagnostic Steps:

• Check for any other related trouble codes and address them first.
• Inspect the wiring and connectors associated with the high-resolution signal circuit for damage or corrosion.
• Test the crankshaft position sensor (CKP) and camshaft position sensor (CMP) for proper operation.
• Verify the integrity of the timing chain or belt to ensure it is not stretched or damaged.
• Use an oscilloscope to check the waveform of the high-resolution signal to confirm its accuracy.
• If applicable, update or reprogram the engine control module (ECM) software as per manufacturer recommendations.
• Replace faulty components if necessary based on diagnostic findings.