P2227

P2227-BAROMETERIC PRESSURE SENSOR RATIONALITY

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

Theory of Operation

The barometric pressure is measured by the Inlet Air Temperature/Pressure Sensor, which is located on the Air Cleaner Assembly. There is a key on check and a rationality check. At key on, the readings for the Boost Pressure Sensor, Exhaust Gas Pressure Sensor, and Inlet Air Pressure Sensor are compared. This fault code occurs if the inlet air pressure reading is different from the other two. During normal engine operation the rationality check verifies the inlet air pressure is reading an unreasonable value for a calibrated period of time then an error is recorded. The key-on portion of the rationality will light the MIL immediately after the diagnostic runs and fails. The rationality portion is a two trip fault. During this time the ECM uses an estimated barometric pressure. The ECM turns off the MIL when the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:
Key on.

- Set Condition:
The ECM does not read a change in value from the sensor over time.





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

1. INLET TEMPERATURE/PRESSURE SENSOR
1. Turn the ignition on.
2. Wait 5 seconds after ignition is turned ON, using the scan tool, check DTCs

Is P2227 stored?

Yes

- Go To 2

No

- Replace the Inlet Air Temperature/Pressure Sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

2. INTERMITTENT CONDITION
1. Erase the DTC with the scan tool.
2. Start the engine and let it idle for 1 minute. With the scan tool in sensors, monitor the Inlet Air Pressure Sensor reading.

Does the value fluctuate slightly, indicating the sensor is not stuck?

Yes

- Refer to the INTERMITTENT CONDITION - DIESEL (Diagnostic Procedure). Intermittent Condition Test

No

- Replace the Inlet Air Temperature/Pressure Sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test