P2229
DTC P2228 or P2229
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC P2228
- Barometric Pressure (BARO) Sensor Circuit Low Voltage
DTC P2229
- Barometric Pressure (BARO) Sensor Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The barometric pressure (BARO) sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The engine control module (ECM) supplies 5 volts to the BARO sensor on a 5-volt reference circuit, and provides a ground on a low reference circuit. The BARO sensor provides a voltage signal to the ECM on a signal circuit relative to barometric pressure changes.
Conditions for Running the DTC
P2228-Key On Test
* DTCs P0120, P0121, P0122, P0123, P0220, P0222 or P0223 are not set.
* The ignition is ON.
* This DTC runs continuously when the above conditions are met.
P2228-Engine Running Test
* DTCs P0120, P0121, P0122, P0123, P0220, P0222 or P0223 are not set.
* The throttle position is greater than or equal to 0 percent and the engine speed is less than or equal to 800 RPM.
OR
The throttle position is greater than or equal to 12.5 percent and then engine speed is greater than 800 RPM.
* This DTC runs continuously when the above conditions are met.
P2229
* DTCs P0120, P0121, P0122, P0123, P0220, P0222, or P0223 are not set.
* The engine is running.
* The engine run time is greater than 4 minutes.
* The startup coolant temperature is between -30°C and +30°C (-22°F and +86°F).
* The throttle position is less than 1 percent.
* The engine speed is greater than 1,200 RPM.
* This DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
P2228
The BARO is less than 8 kPa for less than 1 minute.
P2229
The BARO is greater than 199 kPa for less than 1 minute.
Action Taken When the DTC Sets
DTCs P2228 and P2229 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P2228 and P2229 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
* Measuring Frequency (Component Tests and General Diagnostics)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
J 35555 Metal Mityvac
Circuit/System Verification
1. Verify that the following DTCs are not set: P0641 or P0651.
• If any of the DTCs are set, refer to DTC P0641 or P0651 (P0641) .
2. Ignition ON, observe the BARO parameter with a scan tool. The BARO parameter should be within the range specified in the altitude vs. barometric pressure table. Refer to Altitude Versus Barometric Pressure (Altitude Versus Barometric Pressure) .
3. 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. Ignition OFF, disconnect the harness connector at the BARO sensor.
2. Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference circuit terminal A of the connector and a good ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
• If less than the specified range, test the 5-volt reference circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the ECM.
• If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
4. Verify the scan tool BARO sensor voltage parameter is less than 15 kPa.
• If greater than the specified range, tests the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
5. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool BARO sensor parameter is greater than 190 kPa.
• If less than the specified range, test the sensor signal circuit for an open/high resistance or a short to ground.
6. If all circuits test normal, test or replace the BARO sensor.
Component Testing
Important: You must perform the Circuit/System Testing before proceeding with the Component Test.
1. Ignition ON, engine OFF, remove the BARO sensor.
2. Install a 3A fused jumper wire between the 5-volt reference terminal C of the sensor and 5-volt reference.
3. Install a jumper wire between the low reference terminal A of the sensor and ground.
4. Install a jumper wire at the signal terminal B of the BARO sensor.
5. Connect a DMM between the jumper wire from terminal B of the sensor and ground.
6. Install the J 35555 to the BARO sensor vacuum port. Slowly apply vacuum to the sensor while monitoring the voltage on the DMM. The voltage should vary between 5.2-0 volts, without any spikes or dropouts.
• If the voltage is not within the specified range or is erratic, replace the BARO sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Barometric Pressure Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming