P2227
DTC P2227
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P2227
- Barometric Pressure (BARO) Sensor Performance
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The barometric pressure (BARO) sensor measures the pressure of the atmosphere. This pressure is affected by altitude and weather conditions. A diaphragm within the BARO sensor is displaced by the pressure changes that occur from varying altitudes and weather conditions. The sensor translates this diaphragm action into the voltage signal input that is used by the engine control module (ECM) for diagnostics, emissions control, and to calculate fuel delivery.
The ECM provides the BARO sensor with a 5 V reference circuit, a low reference circuit and a signal circuit. The BARO sensor provides a voltage signal to the ECM relative to barometric pressure changes.
Conditions for Running the DTC
* DTC P0068, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P0220, P0222, P0223, P1516, P2101, P2135, P2228, or P2229 is not set.
* The ignition is ON for greater than 10 s.
* The vehicle speed is greater than 100 km/h (62 mph).
Conditions for Setting the DTC
The ECM detects that the difference between the current BARO sensor reading and the previous BARO sensor reading is greater than 10 kPa (1.5 psi) for 5 s.
Action Taken When the DTC Sets
DTC P2227 is a Type B DTC.
Conditions for Clearing the MIL/DTC
DTC P2227 is a Type B DTC.
Reference Information
Schematic Reference
Engine Controls Schematics (LS3) [1][2]Electrical DiagramsEngine Controls Schematics (LS7) [1][2]Electrical DiagramsEngine Controls Schematics (LS9) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views 5 Bow Lowered Switch (CM7)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
GE 23738-A - Vacuum Pump
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
1. Verify that DTC P2228, or P2229 is not set.
• If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
• If none of the DTCs are set
2. Ignition ON
3. Verify the scan tool BARO parameter remains constant and is within the range specified in the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.
• If not constant or not within the specified range
Refer to Circuit/System Testing
• If constant and within the specified range
4. Operate the vehicle within the Conditions for Running the DTC to verify that the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
5. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing
• If the DTC does not set
6. All OK
Circuit/System Testing
1. Verify none of the conditions listed below exist with the B17 BARO sensor:
* Moisture or debris in the inlet port
* Damage
• If a condition exists
Repair the condition or replace the B17 BARO sensor as necessary.
• If none of the conditions exist
2. Test or replace the B17 BARO sensor.
Component Testing
Note: You must perform the Circuit/System Testing before proceeding with the Component Test.
Erratic Signal Test
1. Ignition OFF, remove the B17 BARO sensor.
2. Install a 3 A fused jumper between the harness connector 5 V reference circuit terminal 1 and terminal 1 of the sensor. Install a jumper wire between the low reference terminal 2 of the sensor and ground.
3. Ignition ON, test for 5.2-0 V without any spikes or dropouts between the signal terminal 3 and the low reference terminal 2 while slowly applying vacuum to the sensor with the GE 23738-A.
• If not between 5.2 and 0 V or has spikes or dropouts
Replace the B17 BARO sensor
• If between 5.2 and 0 V and there are no spikes or dropouts
4. All OK
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Barometric Pressure Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming, and setup