DTC P0338 Crankshaft Position Sensor A Circuit High Input

In the world of automotive diagnostics, On-Board Diagnostic Trouble Codes (DTCs) play a vital role in identifying issues within your vehicle. In this comprehensive guide, we will delve into DTC P0338, specifically the Crankshaft Position Sensor A Circuit High Input problem. We will decode its meaning, explore common symptoms, investigate potential causes, guide you through the diagnostic process, and provide effective solutions for resolving this trouble code. Let’s begin.

1. What does P0338 code mean?

DTC P0338 is an On-Board Diagnostic Trouble Code that signals a high input signal from the Crankshaft Position Sensor A Circuit. The crankshaft position sensor is essential for monitoring the engine’s position and rotational speed. When the Engine Control Module (ECM) detects a high input signal from this sensor, it triggers the P0338 code, indicating a problem with the sensor or its circuit.

2. What are the causes of DTC P0338?

Understanding the potential causes of DTC P0338 is the first step in effective troubleshooting. These causes may include:

  • A malfunctioning or damaged crankshaft position sensor.
  • Wiring issues such as shorts, breaks, or poor connections in the sensor’s circuit.
  • Corroded or damaged connectors.
  • An ECM problem, though this is relatively rare.

Identifying the root cause is crucial to addressing the issue accurately.

3. What are the symptoms of DTC P0338?

Recognizing the symptoms associated with DTC P0338 is essential for early detection. Common signs of this issue include:

  • Engine misfires or hesitation during acceleration.
  • Difficulty starting the engine or prolonged cranking time.
  • Reduced engine performance.
  • An illuminated check engine light (CEL) on the dashboard.

If you experience any of these symptoms, addressing the problem promptly is essential to prevent further damage.

4. How to diagnose DTC P0338?

Accurate diagnosis of DTC P0338 requires a systematic approach. Here’s a step-by-step guide:

If your initial inspection and basic multimeter testing don’t reveal the cause of DTC P0338, 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 P0338 problem?

Once you’ve identified the issue causing DTC P0338, it’s time to address it effectively. Here are some steps to consider:

  • Replace the crankshaft position sensor if it is faulty or damaged.
  • Repair or replace any damaged wiring or connectors in the Crankshaft Position Sensor A Circuit.
  • Ensure proper electrical connections and clean corroded connectors.
  • Clear the trouble code using your OBD-II scanner after completing repairs.

Clearing the trouble code is essential to reset the check engine light and confirm that the problem has been successfully resolved.


In this comprehensive guide, we’ve explored DTC P0338, the Crankshaft Position Sensor A Circuit High Input code. Understanding its meaning, symptoms, potential causes, systematic diagnosis, and the importance of clearing the trouble code empowers you to address this issue with confidence. Whether you’re an automotive enthusiast or a professional mechanic, resolving these problems with precision and expertise not only restores your vehicle’s performance but also enhances your automotive knowledge. Safe and smooth travels!