DL1 - Induce DTC 337

DTC 327 indicates the Pressure Feedback EGR (PFE) / Differential Pressure Feedback EGR (DPFE) sensor signal is less than the Self-Test minimum value of 0.2 volt.

Possible causes:

- Damaged PFE/DPFE sensor.

- Open harness circuits.

- Shorted harness circuits.

- Damaged Powertrain Control Module (PCM).

- Key "OFF".

- Disconnect PFE/DPFE sensor.

- Jumper VREF circuit to PFE/DPFE circuit at PFE/DPFE sensor vehicle harness connector.

- Rerun Key On, Engine Off (KOEO) Self-Test. Quick Test Appendix (Detailed Testing Instructions)

NOTE: If no DTCs are generated, immediate remove jumper and go directly to Step DL4.

- Is DTC 337 present (ignore all other DTCs)?

Yes -- Replace PFE/DPFE sensor. Remove jumper. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Remove jumper. Go to DL2. DL2 - Measure VREF Circuit Voltage at PFE/DPFE Sensor