P2227

DTC P2227, P2228, or P2229 (LAU)

Diagnostic Instructions

- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic approach.
- Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P2227
Barometric Pressure (BARO) Sensor Performance

DTC P2228
Barometric Pressure (BARO) Sensor Circuit Low Voltage

DTC P2229
Barometric Pressure (BARO) Sensor Circuit High Voltage

Circuit/System Description

The barometric pressure (BARO) sensor responds to changes in altitude and atmospheric conditions. This gives the engine control module (ECM) an indication of barometric pressure. The ECM uses this information to calculate fuel delivery. The BARO sensor is located within the controller and is not serviced as a separate unit. The BARO sensor provides a voltage signal to the ECM relative to the atmospheric pressure changes. The ECM monitors the BARO sensor signal for a voltage outside of the normal range.

Conditions for Running the DTC

P2227

- Before the ECM can report DTC P2227 failed, DTCs P0100, P0101, P0102, P0103, P0111, P0112, P0113, P0114, P0121, P0122, P0123, P0221, P0222, P0223, P0236, P0237, P0238, P2228, and P2229 must run and pass.
- The engine is operating.
- The engine speed is less than 1,120 RPM.
- The throttle position sensor parameter is less than 10 %.
- DTC P2227 runs whenever the above conditions are met.

P2228 or P2229

- The ignition is ON.
- The DTCs run continuously when the above condition is met for 0.2 s.

Conditions for Setting the DTC

P2227

- The ECM detects that the BARO sensor signal plus a calibrated threshold is less than the boost pressure sensor signal plus a calibrated threshold for more than 9 s.
OR
- The ECM detects that the BARO sensor signal plus a calibrated threshold greater than the boost pressure sensor signal plus a calibrated threshold for more than 9 s.
OR
- The ECM detects that the BARO pressure changed greater than 5 kPa (0.7 psi) within 20 s.
OR
- The ECM detects that the BARO pressure changed greater than 10 kPa (1.5 psi) since the last ignition cycle.

P2228

- The ECM detects that the BARO sensor voltage is less than 0.20 V for 0.5 s.
OR
- The ECM detects that the BARO sensor signal is less than 45 kPa (6.5 psi) for 2 s

P2229

- The ECM detects that the BARO sensor voltage is greater than 4.8 V for 0.5 s.
OR
- The ECM detects that the BARO sensor signal is greater than 115 kPa (16.7 psi) for 2 s.

Action Taken When the DTC Sets

DTCs P2227, P2228, and P2229 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2227, P2228, and P2229 are Type B DTCs.

Reference Information

Schematic Reference Engine Controls Schematics

Connector End View Reference
Component Connector End Views

DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference
Control Module References for scan tool information

Circuit/System Verification

1. Start the engine. Check the DTC information with a diagnostic tool. DTCs P2227, P2228 or P2229 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Inspect the atmospheric vent on the K20 ECM case for one of the following conditions:
- Moisture in the vent inlet
- Debris in the vent inlet

2. If a condition exists, attempt to clean or dry the atmospheric inlet.
3. Start the engine. Check the DTC information with a diagnostic tool. DTCs P2227, P2228 or P2229 should not set.
4. If DTC P2227, P2228, or P2229 sets, replace the K20 ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming