P1406 – OBD-II DTC

OBD-II DTC P1406 – DPFE Circuit High Input

DTC P1406 meaning

DTC P1406 refers to a problem with the DPFE (Differential Pressure Feedback EGR) circuit, indicating a high input signal. This code is triggered when the Engine Control Module (ECM) detects that the voltage from the DPFE sensor is higher than expected, which can affect the operation of the Exhaust Gas Recirculation (EGR) system.

DTC P1406 symptoms

Common symptoms associated with DTC P1406 may include:

• Illuminated Check Engine Light
• Reduced engine performance
• Increased emissions
• Rough idling or stalling
• Poor fuel economy

DTC P1406 causes

Several factors can lead to the triggering of DTC P1406, including:

• Faulty DPFE sensor
• Wiring issues or short circuits in the DPFE circuit
• Blocked or restricted EGR passages
• Faulty EGR valve
• Vacuum leaks in the intake system

DTC P1406 seriousness

DTC P1406 can be considered serious as it affects the EGR system’s functionality, which is crucial for reducing emissions and maintaining engine performance. Ignoring this code may lead to further engine issues, increased emissions, and potential damage to other components.

How to diagnose DTC P1406

To diagnose DTC P1406, follow these steps:

1. Use an OBD-II scanner to confirm the DTC and check for any additional codes.
2. Inspect the DPFE sensor and its wiring for any visible damage or corrosion.
3. Test the DPFE sensor’s voltage output with a multimeter to ensure it is within specifications.
4. Check for any vacuum leaks in the EGR system and intake manifold.
5. Inspect the EGR valve for proper operation and blockage.

How to fix DTC P1406 step-by-step instructions

To fix DTC P1406, follow these steps:

1. Repair or replace any damaged wiring or connectors related to the DPFE sensor.
2. Replace the faulty DPFE sensor if it is not functioning correctly.
3. Clean or replace the EGR valve if it is blocked or malfunctioning.
4. Clear any blockages in the EGR passages to ensure proper flow.
5. Recheck the system for leaks and ensure all connections are secure.

How to erase DTC P1406

To erase DTC P1406, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the “Erase Codes” or “Clear Codes” function on the scanner.
3. Confirm the action to clear the DTC from the ECM.
4. Disconnect the scanner and start the engine to check if the code reappears.

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