P040B

P040B-EXHAUST GAS RECIRCULATION TEMPERATURE SENSOR 1 CIRCUIT PERFORMANCE





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams. Electrical Diagrams

Theory of Operation

The Exhaust Gas Recirculation (EGR) Outlet Temperature Sensor is a variable resistor sensor and is used to measure the temperature of the EGR gas flow after it exits the EGR Valve. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the EGR outlet temperature. There is a Key-on and calibration test which requires an eight hour ignition off time. The Key-on test fails if the EGR Orifice Temperature is greater than a calibrated threshold at Key-on. The calibration test fails if the EGR Orifice Temperature falls below a calibrated threshold for a calibrated period of time after certain conditions have been met. The ECM turns on the MIL when the diagnostic runs and fails in two consecutive drive cycles.

- When Monitored:
At ignition on and when engine is running.

- Set Condition:
The key-on test fails if the EGR Outlet Temperature Sensor value is greater than a calibrated threshold at Key-on. The other rationality test fails if the EGR Orifice Temperature value falls below a calibrated threshold for a calibrated period of time after certain conditions have been met.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
EXHAUST GAS RECIRCULATION TEMPERATURE SENSOR

NOTE: Repair any EGR Cooler Bypass Valve DTCs before proceeding with this test.

1. Turn the ignition off.
2. Disconnect the EGR temperature sensor harness connector.

NOTE: Check connectors - Clean/repair as necessary.

3. Remove the EGR Outlet Temperature Sensor and reconnect the wiring harness connector to the sensor.
4. Turn the Ignition on, engine off.
5. Monitor scan tool, while heating the sensor with an external heat source (DO NOT USE OPEN FLAME).

Does the reading from the sensor increase at least 2.78°C (5°F) on the scan tool?

Yes

- Turn the ignition off. Clean the EGR Outlet Temperature Sensor and reinstall.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Replace EGR Outlet Temperature Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.