P046C

P046C-EGR POSITION SENSOR PERFORMANCE




For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation

The Exhaust Gas Recirculation (EGR) Valve is opened by a motor located on top of the EGR Valve. The EGR Valve is spring loaded and is normally closed. The motor electronically opens the valve and is controlled by the PCM. The PCM monitors three functions of the EGR Valve; the commanded position, actual position, and an acceptable tolerance between the actual and commanded position. If the difference between the actual and commanded positions exceeds a calibrated threshold over a period of time, then the fault will set. If the error is set in 2 consecutive drive cycles the system will set the MIL Lamp. After the diagnostic runs and passes on four consecutive drive cycles, the MIL Lamp will clear.

- When Monitored:
At key on, and with engine running.

- Set Condition:
EGR valve is not able to reach the commanded position over a calibrated period of time.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC

NOTE: If there are any DTCs present for the Boost Pressure Sensor or EGR Temperature Sensor, perform the diagnostics for those DTCs before proceeding with this test procedure.

1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 30 seconds.
5. Start the vehicle. It may be necessary to drive vehicle to reset DTC.
6. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION - 6.7L. Intermittent Condition Test

2. CHECK THE EGR CONTROL CIRCUITS FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the EGR Valve harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance of the (K682) EGR Control 1 circuit between the EGR Valve harness connector and the PCM harness connector.
5. Measure the resistance of the (K684) EGR Control 2 circuit between the EGR Valve harness connector and the PCM harness connector.
6. Measure the resistance of the (K686) EGR Control 3 circuit between the EGR Valve harness connector and the PCM harness connector.

Is the resistance below 5.0 Ohms for each circuit?

Yes

- Go To 3

No

- Repair the open or high resistance in the circuit that measured above 5.0 Ohms.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

3. CHECK THE EGR POSITION SIGNAL CIRCUITS FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K683) EGR Position Signal 1 circuit between the EGR Valve harness connector and the PCM harness connector.
2. Measure the resistance of the (K685) EGR Position Signal 2 circuit between the EGR Valve harness connector and the PCM harness connector.
3. Measure the resistance of the (K687) EGR Position Signal 3 circuit between the EGR Valve harness connector and the PCM harness connector.

Is the resistance below 5.0 Ohms for each circuit?

Yes

- Go To 4

No

- Repair the open or high resistance in the circuit that measured above 5.0 Ohms.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

4. CLEAN THE EGR VALVE
1. Reconnect the PCM C1 harness connector.
2. Remove and clean the EGR Valve. Procedures.
3. Reconnect the EGR Valve harness connector.
4. Turn the ignition on.
5. With the scan tool, erase DTCs.
6. Turn the ignition off for 75 seconds.
7. Start the vehicle. It may be necessary to drive vehicle to reset DTC.
8. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Go To 5

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

5. REPLACE THE EGR VALVE
1. Replace the EGR Valve. Exhaust Gas Recirculation (EGR) Valve - Removal.
2. Turn the ignition on.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Start the vehicle. It may be necessary to drive vehicle to reset DTC.
6. With the scan tool, read DTCs.

Did the DTC return?

Yes

- Replace the Powertrain Control Module. Powertrain Control Module - Removal
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.