P0407 – OBD-II DTC

OBD-II DTC P0407 – Exhaust Gas Recirculation Sensor A Circuit High

DTC P0407 meaning

DTC P0407 refers to a problem with the Exhaust Gas Recirculation (EGR) sensor circuit. Specifically, it indicates that the voltage signal from the EGR sensor is higher than expected, which suggests a malfunction in the EGR system. The EGR system is responsible for recirculating a portion of the exhaust gases back into the engine’s intake to reduce nitrogen oxide emissions and improve fuel efficiency.

DTC P0407 symptoms

Common symptoms associated with DTC P0407 may include:

• Check Engine Light illuminated
• Reduced engine performance
• Increased fuel consumption
• Rough idling or stalling
• Failed emissions test

DTC P0407 causes

Several factors can lead to the triggering of DTC P0407, including:

• Faulty EGR sensor
• Wiring issues or short circuits in the EGR sensor circuit
• Clogged EGR passages
• Faulty engine control module (ECM)
• Vacuum leaks affecting the EGR system

DTC P0407 seriousness

DTC P0407 is considered a moderate to serious issue. While it may not cause immediate engine failure, it can lead to:

• Increased emissions
• Decreased fuel efficiency
• Potential damage to the engine over time
• Failure to pass emissions testing

How to diagnose DTC P0407

To diagnose DTC P0407, follow these steps:

1. Use an OBD-II scanner to confirm the DTC and check for any additional codes.
2. Inspect the EGR sensor and its wiring for any visible damage or corrosion.
3. Test the EGR sensor voltage and compare it to manufacturer specifications.
4. Check for vacuum leaks in the EGR system.
5. Examine the EGR passages for clogs or restrictions.
6. Perform a functional test of the EGR system to ensure it operates correctly.

How to fix DTC P0407 step-by-step instructions

To fix DTC P0407, follow these steps:

1. Clear the DTC using an OBD-II scanner.
2. If the code reappears, replace the faulty EGR sensor.
3. Repair any damaged wiring or connectors in the EGR sensor circuit.
4. Clean or replace clogged EGR passages.
5. Check and repair any vacuum leaks in the EGR system.
6. Recheck the EGR system operation and ensure it meets specifications.

How to erase DTC P0407

To erase DTC P0407, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase codes.
4. Confirm the action and wait for the scanner to indicate that the codes have been cleared.
5. Disconnect the scanner and start the engine to ensure the Check Engine Light remains off.