DTC P0389 Crankshaft Position Sensor B Circuit Intermittent

In the intricate realm of automotive diagnostics, On-Board Diagnostic Trouble Codes (DTCs) serve as valuable tools to uncover and rectify issues within our vehicles. In this comprehensive blog post, we will delve into the nuances of DTC P0389, specifically focusing on the Crankshaft Position Sensor B Circuit Intermittent problem. Whether you’re a dedicated automotive enthusiast or a seasoned mechanic, this guide will provide you with the knowledge and steps to diagnose and address this particular intermittent trouble code. Let’s explore the world of intermittent challenges.

1. Understanding P0389: Deciphering the Code

DTC P0389 is a diagnostic trouble code that indicates an intermittent issue in the Crankshaft Position Sensor B Circuit. The Crankshaft Position Sensor, a crucial component of the engine management system, continuously monitors the position and rotational speed of the crankshaft. When it intermittently fails to provide a consistent signal, the Engine Control Module (ECM) triggers the P0389 code, signaling a potential problem with the sensor or its circuit that comes and goes.

2. Investigating the Causes: What Triggers P0389?

To effectively diagnose and resolve DTC P0389, it’s essential to understand the various potential causes, which may include:

  • A malfunctioning or damaged crankshaft position sensor.
  • Intermittent wiring issues, such as loose connections, occasional shorts, or corroded contacts in the sensor’s circuit.
  • Irregular electrical connections or connector corrosion.
  • Rare instances of intermittent problems with the ECM. Identifying the underlying issue is crucial for successful resolution.

3. Recognizing the Symptoms: What to Be On the Lookout For

Recognizing the symptoms associated with DTC P0389 can be challenging due to its intermittent nature. Common signs of this issue when it occurs include:

  • Intermittent engine misfires or hesitation during acceleration.
  • Occasional difficulty starting the engine, especially in unpredictable conditions.
  • An illuminated check engine light (CEL) on the dashboard that may appear and disappear.
  • Infrequent moments of reduced engine performance and power. Given the intermittent nature of the code, it’s crucial to monitor your vehicle closely for these symptoms.

4. Diagnosing DTC P0389: A Systematic Approach

Accurate diagnosis of DTC P0389 necessitates a systematic approach that can capture the intermittent nature of the problem. Here’s a step-by-step guide to help you pinpoint the issue:

  • Initiate the diagnostic process by using an OBD-II scanner to retrieve the trouble code, even if the CEL is currently off.
  • Perform a thorough visual inspection of the crankshaft position sensor and its wiring for visible damage or loose connections.
  • Utilize a multimeter to test the sensor’s resistance, especially during different operating conditions.
  • Assess the wiring and connectors within the Crankshaft Position Sensor B Circuit for continuity, focusing on any potential intermittent issues. Consider driving the vehicle under various conditions to replicate the intermittent fault.

5. Resolving P0389: How to Tackle the Intermittent Problem

Once you’ve identified the issue causing DTC P0389, it’s time to address it effectively, bearing in mind its intermittent nature. Consider these steps:

  • Replace the crankshaft position sensor if it is confirmed to be faulty or showing intermittent behavior.
  • Repair or replace any damaged wiring or connectors in the Crankshaft Position Sensor B Circuit, ensuring secure connections.
  • Thoroughly clean and inspect connectors for corrosion.
  • Test the vehicle under different conditions to verify that the intermittent issue has been resolved.
  • Clear the trouble code using your OBD-II scanner and continue monitoring the vehicle for any recurrence. Effective resolution of an intermittent issue may require patience and careful observation.


In this comprehensive guide, we’ve navigated through DTC P0389, the Crankshaft Position Sensor B Circuit Intermittent code. Understanding its meaning, potential causes, symptoms, systematic diagnosis, and the unique challenges posed by intermittent issues empowers you to confidently address this code. Whether you’re a dedicated automotive enthusiast or a skilled mechanic, mastering the art of resolving intermittent challenges not only restores your vehicle’s performance but also elevates your automotive expertise. Here’s to smooth and reliable journeys ahead!