P0012 Fault Code

P0012 OBD-II Trouble Code Short Description

"A" Camshaft Position - Timing Over-Retarded (Bank 1)

What does trouble code P0012 mean?

The P0012 fault code refers to the "A" Camshaft Position - Timing Over-Retarded (Bank 1). This means that the engine control module (ECM) has detected that the camshaft timing for cylinder bank 1 is running too late in relation to the crankshaft position.

When this fault code is triggered, it usually indicates a problem with the variable valve timing (VVT) system. The VVT system is responsible for adjusting the timing of the camshaft(s) to optimize engine performance and fuel efficiency.

There are a few possible causes for this fault code. It could be due to a faulty camshaft position sensor, a malfunctioning VVT solenoid, a problem with the timing chain or belt, or issues with the oil flow and pressure.

To diagnose and solve the issue, it is recommended to perform the following steps:

  1. Check the engine oil level and ensure it is at the correct level. Low oil pressure or dirty oil can affect the VVT system's operation.

  2. Inspect the wiring and connectors related to the camshaft position sensor and VVT solenoid for any signs of damage or corrosion. Repair or replace as necessary.

  3. Test the camshaft position sensor and VVT solenoid using a scan tool or multimeter to ensure they are functioning properly. Replace any faulty components.

  4. Check the timing chain or belt for any wear or damage. If necessary, replace the timing components following the manufacturer's recommended procedures.

  5. Clear the fault codes using a scan tool after any repairs and take the vehicle for a test drive to verify if the issue has been resolved.

It is essential to address the P0012 fault code promptly as prolonged operation with timing issues can lead to engine damage and reduced performance. If unsure or unable to diagnose the problem yourself, it is recommended to seek the assistance of a qualified mechanic.


What are the symptoms of the P0012 code?

The P0012 fault code indicates an issue with the "A" camshaft position being over-retarded in timing on Bank 1. Some common symptoms associated with this fault code include:

  • Check engine light (MIL) illuminated
  • Engine running rough or misfiring
  • Decreased fuel efficiency
  • Loss of power or acceleration
  • Rough idle
  • Engine stalls or struggles to start

Please note that these symptoms may vary depending on the make, model, and year of the vehicle. It is always recommended to consult with a qualified mechanic or use an OBD-II scanner to properly diagnose and troubleshoot the issue.


What causes the P0012 code?

The P0012 fault code on cars is usually caused by a problem with the camshaft position timing being over-retarded on bank 1. Some possible causes of this fault code include:

  • Faulty camshaft position sensor
  • Malfunctioning Variable Valve Timing (VVT) system
  • Timing chain or belt stretch or damage
  • Low engine oil level or poor quality oil
  • Clogged or restricted oil passages
  • Faulty Engine Control Module (ECM)

It is important to diagnose and repair the underlying issue causing the fault code in order to resolve the problem and prevent further damage to the engine. It is recommended to consult a professional mechanic or use a diagnostic tool to determine the exact cause of the P0012 fault code.

Possible Solutions

How to fix P0012?

To fix the P0012 fault code, which refers to the "A" Camshaft Position - Timing Over-Retarded (Bank 1), you can follow these steps:

  1. Check the oil level: Ensure that the engine has enough oil and that it is clean and free from debris. Low or dirty oil can affect the functioning of the camshaft timing system.

  2. Inspect the timing belt or chain: Check the condition of the timing belt or timing chain. Look for any signs of wear, damage, or slack. Replace the timing belt or chain if necessary.

  3. Examine the camshaft position sensor: Inspect the camshaft position sensor for any damage or loose connections. Clean or replace the sensor if needed.

  4. Verify the crankshaft position sensor: Check the crankshaft position sensor for any issues. Ensure that it is properly aligned and functioning correctly. Clean or replace the sensor if necessary.

  5. Inspect the Variable Valve Timing (VVT) system: Check the VVT system components such as the solenoid, oil control valve, or actuator. Clean or replace any parts that are not working properly.

  6. Perform an engine relearn procedure: Reset the Engine Control Unit (ECU) by disconnecting the battery for about 15 minutes. Reconnect the battery and start the vehicle. Allow the engine to idle for a few minutes and then take it for a short drive.

  7. Get professional help: If you are unsure about any of the above steps or if the fault code persists after performing them, it is recommended to seek assistance from a qualified mechanic who can diagnose and repair the issue accurately.

Please note that these steps provide a general guideline, and the exact troubleshooting steps may vary depending on the make and model of your vehicle.