Diagnostic Test

VISUAL INSPECTION
1. Turn the ignition off.
2. Visually inspect the Exhaust Differential Pressure Sensor for physical damage, proper electrical connection and proper mechanical connection. Ensure any tubes and/or hoses connected to the sensor are in good working condition and properly connected at all ends.
3. Visually inspect the entire exhaust system for bent, crushed or otherwise damaged tubes which may cause an exhaust system restriction.
4. Inspect the exhaust system for exhaust leaks.
  Were any problems found?
  
  Yes
  - Repair or replace as necessary.
  No
  - Go to step 2
PARTICULATE FILTER REGENERATION
1. Start and idle the engine.
2. With the scan tool, Clear DTCs in the Engine Control Module (ECM).
3. With the scan tool, perform the Diesel Particulate Filter Regeneration procedure.
4. After this procedure is complete, turn the ignition off for 60 seconds.
5. Test drive the vehicle.
6. With the scan tool, Read DTCs in the Engine Control Module (ECM).
  Is the status Active for this DTC?
  
  Yes
  - Go to step 3
  No
  - Test complete.
EXHAUST DIFFERENTIAL SENSOR CIRCUIT HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Exhaust Differential Pressure Sensor harness connector.
3. Disconnect the ECM harness connectors.
4. Measure the resistance of each Exhaust Differential Pressure Sensor circuit between the Exhaust Differential Pressure Sensor harness connector and the ECM harness connector.
  Is the resistance below 10.0 ohms for each circuit?
  
  Yes
  - Go to step 4
  No
  - Repair the circuit(s) that measured above 10.0 ohms for high resistance. See DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure
EXHAUST DIFFERENTIAL PRESSURE SENSOR
1. Turn the ignition off.
2. Replace the Exhaust Differential Pressure Sensor.
3. Turn the ignition on.
4. With the scan tool, Clear DTCs in the Engine Control Module (ECM).
5. Test drive the vehicle
6. With the scan tool, Read DTCs in the Engine Control Module (ECM).
  Is the status Active for this DTC?
  
  Yes
  - Replace the Diesel Particulate Filter.
  No
  - Test Complete.