DTC P0379 Timing Reference High Resolution Signal B No Pulses

Welcome to this informative blog post dedicated to resolving On-Board Diagnostic Trouble Code P0379: Timing Reference High Resolution Signal B No Pulses. As an Automotive Enthusiast and a Certified Automotive Technician, my mission is to provide you with valuable insights and practical guidance for tackling automotive issues effectively. In the following sections, we’ll dive into the meaning of DTC P0379, explore its associated symptoms, identify potential causes, delve into diagnostic methods, and discuss how to successfully resolve this problem.

1. What does P0379 code mean?

Let’s begin by deciphering the significance of DTC P0379. Within the realm of automotive diagnostics, “P0379” is a standardized code used by your vehicle’s onboard computer (OBD-II system) to indicate a specific issue. The “P” designates it as a Powertrain-related problem, often linked to the engine or transmission. The “0379” is the unique trouble code signifying Timing Reference High Resolution Signal B No Pulses.

In simpler terms, this trouble code serves as an alert that the Timing Reference High Resolution Signal B is not providing any pulses. This signal plays a critical role in synchronizing various engine components and maintaining precise timing for optimal performance.

2. What are the causes of DTC P0379?

Now, let’s explore the potential causes behind DTC P0379:

  • Faulty Timing Reference Sensor: The sensor responsible for generating Timing Reference High Resolution Signal B may be malfunctioning or damaged.
  • Wiring or Connector Issues: Damaged, corroded, or loose wiring and connectors in the sensor circuit can disrupt the signal.
  • Sensor Alignment Problems: Incorrect sensor installation or improper alignment can lead to a lack of signal pulses.
  • Power Supply Problems: Issues with the power supply to the sensor circuit can result in a failure to generate pulses.
  • Engine Mechanical Issues: In some cases, engine mechanical problems can indirectly affect the sensor’s performance.

3. What are the symptoms of DTC P0379?

Recognizing the symptoms associated with this trouble code is essential for diagnosis. Common signs of DTC P0379 may include:

  • Check Engine Light (CEL): The most noticeable indicator is the illumination of the check engine light on your dashboard.
  • Engine Performance Issues: You may experience engine misfires, poor acceleration, or reduced overall performance due to the absence of signal pulses affecting timing.
  • Difficulty Starting: Your vehicle may have trouble starting or may not start at all due to the absence of timing-related signals.
  • Stalling: The engine may stall intermittently, either while driving or idling, due to the lack of necessary timing signals.

4. How to diagnose DTC P0379?

Diagnosing DTC P0379 requires a systematic approach. Here’s a step-by-step guide:

  • Scan the Code: Utilize an OBD-II scanner to retrieve the trouble code and confirm the issue.
  • Inspect Wiring and Connectors: Thoroughly examine the wiring and connectors related to the timing reference sensor circuit for damage, corrosion, or loose connections.
  • Check Sensor Alignment: Ensure that the sensor is correctly installed and aligned to provide the necessary pulses.
  • Test the Sensor: Assess the sensor’s performance using a digital multimeter to confirm whether it’s generating pulses or not. If your initial inspection and basic multimeter testing don’t reveal the cause of DTC P0379, specialized diagnostic equipment like an oscilloscope or advanced scan tool with live data capabilities can provide more in-depth insights into the sensor’s performance. This advanced testing allows you to detect subtle issues or intermittent faults that might not be evident through simpler diagnostic methods, helping you diagnose and resolve the problem more accurately

5. How to fix DTC P0379 problem?

Now, let’s explore effective strategies for fixing DTC P0379:

  1. Replace the Timing Reference Sensor: If the sensor is malfunctioning or damaged, replace it with a high-quality replacement part.
  2. Repair or Replace Wiring and Connectors: Address any damaged wiring or connectors in the sensor circuit, repairing or replacing them as needed.
  3. Ensure Proper Alignment: Reinstall the sensor, ensuring it’s correctly aligned with the timing reference point.
  4. Check Power Supply: Verify that the power supply to the sensor circuit is stable and within the specified range to ensure pulse generation.
  5. Clear the Trouble Code: After completing the repairs, use your OBD-II scanner to clear the trouble code.
  6. Test Drive: Take your vehicle for a test drive to confirm that the issue has been successfully resolved and that the check engine light remains off.


In conclusion, DTC P0379, indicating Timing Reference High Resolution Signal B No Pulses, can pose challenges, but armed with the knowledge and guidance provided in this article, you’re well-prepared to diagnose and address the issue effectively. Always prioritize safety and, when in doubt, seek professional assistance. Happy troubleshooting on your automotive journey!