P1405: DPFE Sensor Upstream Hose Off Or Plugged

Definition

The OBD2 code P1405 indicates that the Differential Pressure Feedback EGR (DPFE) sensor is detecting a problem, specifically that the upstream hose is either disconnected or blocked, affecting the sensor's ability to measure exhaust gas flow properly

Common causes

Disconnected or damaged DPFE sensor hose
Clogged or blocked upstream hose
Faulty DPFE sensor
Exhaust gas recirculation (EGR) system issues
Vacuum leaks in the system
Corroded or damaged electrical connectors
Improper installation of hoses or sensors

Common misdiagnoses

Faulty DPFE sensor
Clogged EGR valve
Vacuum leaks
Faulty EGR system components
Wiring issues or shorts
Exhaust leaks
Faulty PCM (Powertrain Control Module)

Troubleshooting steps

1. Visual Inspection
2. Check the DPFE sensor and its hoses for any visible signs of damage, disconnection, or blockage
3. Inspect the upstream hose connected to the DPFE sensor for kinks, cracks, or obstructions
4. Check Hose Connections
5. Ensure that the hoses connected to the DPFE sensor are securely attached and not loose
6. Verify that the hoses are connected to the correct ports on the DPFE sensor
7. Inspect the DPFE Sensor
8. Examine the DPFE sensor for any signs of physical damage or corrosion
9. If the sensor appears damaged, consider replacing it
10. Test the DPFE Sensor
11. Use a multimeter to check the voltage output of the DPFE sensor. Compare the readings to the specifications in the vehicle’s service manual
12. If the readings are outside the specified range, the sensor may be faulty and should be replaced
13. Check for Blockages
14. Inspect the EGR system for any blockages, including the EGR valve and passages. A clogged EGR system can cause issues with the DPFE sensor
15. Clean any carbon buildup or debris that may be obstructing the EGR system
16. Inspect the Vacuum Lines
17. Check for any vacuum leaks or damaged vacuum lines that may affect the operation of the EGR system and the DPFE sensor
18. Clear the Code
19. After performing the necessary repairs, clear the trouble code using an OBD-II scanner
20. Take the vehicle for a test drive to see if the code reappears
21. Check for Additional Codes
22. If the P1405 code persists, check for any other related trouble codes that may provide additional insight into the issue
23. Consult the Service Manual
24. Refer to the vehicle’s service manual for specific diagnostic procedures and specifications related to the DPFE sensor and EGR system
25. Seek Professional Help
26. If you are unable to resolve the issue after performing these steps, consider seeking assistance from a qualified mechanic or technician. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P1405 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Visual Inspection

2. Check the DPFE sensor and its hoses for any visible signs of damage, disconnection, or blockage

3. Inspect the upstream hose connected to the DPFE sensor for kinks, cracks, or obstructions

4. Check Hose Connections

5. Ensure that the hoses connected to the DPFE sensor are securely attached and not loose

6. Verify that the hoses are connected to the correct ports on the DPFE sensor

7. Inspect the DPFE Sensor

8. Examine the DPFE sensor for any signs of physical damage or corrosion

9. If the sensor appears damaged, consider replacing it

10. Test the DPFE Sensor

11. Use a multimeter to check the voltage output of the DPFE sensor. Compare the readings to the specifications in the vehicle’s service manual

12. If the readings are outside the specified range, the sensor may be faulty and should be replaced

13. Check for Blockages

14. Inspect the EGR system for any blockages, including the EGR valve and passages. A clogged EGR system can cause issues with the DPFE sensor

15. Clean any carbon buildup or debris that may be obstructing the EGR system

16. Inspect the Vacuum Lines

17. Check for any vacuum leaks or damaged vacuum lines that may affect the operation of the EGR system and the DPFE sensor

18. Clear the Code

19. After performing the necessary repairs, clear the trouble code using an OBD-II scanner

20. Take the vehicle for a test drive to see if the code reappears

21. Check for Additional Codes

22. If the P1405 code persists, check for any other related trouble codes that may provide additional insight into the issue

23. Consult the Service Manual

24. Refer to the vehicle’s service manual for specific diagnostic procedures and specifications related to the DPFE sensor and EGR system

25. Seek Professional Help

26. If you are unable to resolve the issue after performing these steps, consider seeking assistance from a qualified mechanic or technician. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P1405 code