DD1 - Attempt to Generate DTC 337

Diagnostic Trouble Code (DTC) 327 indicates the EGR Position (EGRP) sensor signal is less than the Self-Test minimum.

NOTE: Because the EGRP sensor is preloaded when attached to the EGR valve, a failure in the valve may cause the sensor to lose the preload and set DTC 327.

Possible Causes:
- Damaged EGRP sensor: EGR valve assembly.

- Open in sensor VREF circuit.

- Open in sensor SIG RTN circuit.

- Short to ground in sensor SIG circuit.

- Damaged Powertrain Control Module (PCM).

- Key "OFF".

- Disconnect the EGRP sensor.

- Jumper the VREF circuit to the EGRP sensor SIG circuit at the sensor vehicle harness connector.

- Rerun Key On Engine Off (KOEO) and Key On Engine Running (KOER) Self-Test.

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

Yes -- Replace the EGRP sensor/EGR valve assembly. Remove jumper. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Remove jumper. Go to DD2. DD2 - Measure EGRP VREF Voltage