DTC P0373 Timing Reference High Resolution Signal A Intermittent/Erratic Pulses

Welcome to this comprehensive guide dedicated to troubleshooting On-Board Diagnostic Trouble Code P0373: Timing Reference High Resolution Signal A Intermittent/Erratic Pulses. Whether you’re an automotive enthusiast or a concerned car owner, this article is designed to provide you with valuable insights and practical guidance for addressing this diagnostic trouble code effectively. In the following sections, we’ll delve into the meaning of DTC P0373, identify its symptoms, explore potential causes, discuss diagnosis methods, and provide actionable solutions to resolve the issue.

1. What does P0373 code mean?

Let’s start by decoding the meaning of DTC P0373. Within the realm of automotive diagnostics, “P0373” is a standardized code employed by your vehicle’s onboard computer (OBD-II system) to signal a specific issue. The “P” designates it as a Powertrain-related problem, typically linked to the engine or transmission. The “0373” is the unique trouble code indicating Timing Reference High Resolution Signal A Intermittent/Erratic Pulses.

In simpler terms, this trouble code serves as an indicator that there are irregular or sporadic pulses detected in the Timing Reference High Resolution Signal A. This signal plays a crucial role in synchronizing various engine components and maintaining precise timing for optimal performance.

2. What are the causes of DTC P0373?

Now, let’s explore the potential causes behind DTC P0373:

  • Faulty Timing Reference Sensor: The sensor responsible for generating Timing Reference High Resolution Signal A 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 signal malfunctions.
  • Power Supply Problems: Issues with the power supply to the sensor circuit can result in intermittent signal disruptions.
  • Engine Mechanical Issues: Occasionally, engine mechanical problems can indirectly affect the sensor’s performance.

3. What are the symptoms of DTC P0373?

Identifying the symptoms associated with this trouble code is crucial for diagnosis. Common signs of DTC P0373 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 irregular timing.
  • Occasional Difficulty Starting: Your vehicle may occasionally have trouble starting, or it might not start at all due to erratic timing-related issues.
  • Intermittent Stalling: The engine may intermittently stall while driving or idling due to intermittent signal disruptions.

4. How to diagnose DTC P0373?

Diagnosing DTC P0373 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 a consistent signal.
  • Test the Sensor: Assess the sensor’s performance using a digital multimeter during intermittent signal disruptions. If your initial inspection and basic multimeter testing don’t reveal the cause of DTC P0373, 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 P0373 problem?

Now, let’s explore effective strategies for fixing DTC P0373:

  1. Replace the Timing Reference Sensor: If the sensor is malfunctioning or damaged, replace it with a high-quality replacement.
  2. Repair or Replace Wiring and Connectors: Address damaged wiring or connectors that intermittently cause the issue by repairing or replacing them as necessary.
  3. Ensure Proper Alignment: Reinstall the sensor, making sure 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 during intermittent signal disruptions.
  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 ensure that the issue has been successfully addressed and that the check engine light remains off.


In conclusion, DTC P0373, indicating Timing Reference High Resolution Signal A Intermittent/Erratic Pulses, can present challenges, but with the knowledge and guidance provided in this guide, you’re well-equipped to diagnose and address the issue effectively. Always prioritize safety, and if you’re uncertain, seek professional assistance. Happy troubleshooting on your automotive journey!