P2431
DTC P2430-P2433
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 P2430
- Secondary Air Injection (AIR) System Pressure Sensor Circuit
DTC P2431
- Secondary Air Injection System Pressure Sensor A Circuit Range/Performance
DTC P2432
- Secondary Air Injection System Pressure Sensor A Circuit Low
DTC P2433
- Air Injection System Pressure Sensor A Circuit High
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The secondary air injection (AIR) system aids in the reduction of hydrocarbon emissions during a cold start. The system forces fresh filtered air into the exhaust stream in order to accelerate the catalyst operation. An electric air pump, the secondary AIR injection pump, provides filtered air on demand to the AIR control solenoid valve/pressure sensor assembly. The AIR control solenoid valve/pressure sensor assembly controls the flow of air from the AIR pump to the exhaust manifold. The AIR solenoid relay supplies the current needed to operate the AIR control solenoid valve/pressure sensor assembly. A pressure sensor is used to monitor the air flow from the AIR pump. The engine control module (ECM) supplies the internal pressure sensor with a 5V reference, an electrical ground, and a signal circuit.
The AIR diagnostic uses 3 phases to test the AIR system:
1. DTCs P0411 and P2430 run during Phase 1.
2. DTCs P2430 and P2440 run during Phase 2.
3. DTC P2444 runs during Phase 3.
During phase 1, both the AIR pump and the solenoid valve are activated. Normal secondary air function occurs. Expected system pressure is 8-10 kPa above barometric pressure (BARO).
During phase 2, only the AIR pump is activated. The solenoid valve is closed. Pressure sensor performance and solenoid valve deactivation are tested. Expected system pressure is 20-25 kPa above BARO.
During phase 3, neither the AIR pump nor the solenoid valve is activated. AIR pump deactivation is tested. Expected system pressure equals BARO.
In all 3 phases, testing is accomplished by comparing the measured pressure against the expected pressure. The ECM can detect faults in the AIR pump, AIR control solenoid valve/pressure sensor assembly, and the exhaust check valve. The pressure sensor can also detect leaks and restrictions in the secondary AIR system plumbing.
Conditions for Running the DTC
P2430
* DTCs P0412, P0418, P0606, P1635, P1639, P2432, P2433 are not set.
* More than 60 minutes has elapsed since the last cold start.
* The AIR pump is commanded ON.
* DTC P2430 runs continuously when the above conditions are met.
P2431
* DTCs P0106, P0107, P0108, P0412, P0418, P0606, P1635, P1639, P2432, P2433 are not set.
* The ignition is ON.
* DTC P2431 runs continuously when the above conditions are met.
P2432 and P2433
* DTCs P0606, P1635, P1639 are not set.
* The ignition is ON or the engine is running.
* DTC P2432 and 2433 run continuously when the above conditions are met.
Conditions for Setting the DTC
P2430
The ECM determines that the pressure sensor value change is less than a calibrated value.
P2431
* The ECM determines that the difference between the AIR pressure sensor and the BARO sensor signals is greater than 10 kPa when the AIR pump is commanded OFF.
OR
* The ECM determines that the difference between the AIR pressure sensor and the BARO sensor signals is greater than 50 kPa when the AIR pump is commanded ON.
P2432
The pressure sensor signal is less than 0.2V for at least 12.5 seconds.
P2433
The pressure sensor signal is more than 4.8V for at least 12.5 seconds.
Action Taken When the DTC Sets
DTCs P2430, DTC P2431, DTC P2432, and DTC P2433 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P2430, DTC P2431, DTC P2432, and DTC P2433 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LE5) (Electrical Diagrams)Engine Controls Schematics (LAT) (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Secondary Air Injection System Description (Description and Operation)
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)
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
Circuit/System Verification
1. Ignition ON, command the secondary air injection pump ON and OFF with a scan tool. The air pump should turn ON and OFF.
• If the air pump does not turn ON or OFF, refer to DTC P0411, P0412, P0418, P2440, or P2444 (P0411).
2. Command the secondary air injection solenoid ON and OFF. The solenoid should click with each command.
• If the solenoid does not click, refer to DTC P0411, P0412, P0418, P2440, or P2444 (P0411).
3. Engine running, command the secondary air injection pump ON while observing the secondary air injection pressure sensor parameter. The reading should be 20-25 kPa above the BARO reading.
4. Engine running, command the secondary air injection pump and the secondary air injection solenoid ON while observing the secondary air injection pressure sensor parameter. The reading should be 8-10 kPa above BARO.
5. Ignition ON, engine OFF, observe that the AIR Pressure Sensor parameter is within 3 kPa of the BARO parameter.
• If not the specified range, verify that the BARO parameter is correct for your altitude. Refer to Altitude Versus Barometric Pressure (Altitude Versus Barometric Pressure). If the BARO parameter is not correct for your altitude, refer to DTC P0106 (P0106).
6. 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.
Circuit/System Testing
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing or misdiagnosis may result.
1. Ignition OFF, allow the ECM to completely power down.
2. Disconnect the harness connector at the AIR solenoid valve assembly.
3. Test for less than 5ohm between the low reference circuit terminal 3 and 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.
4. Ignition ON, test for 4.8-5.2V between the 5V reference circuit terminal 1 and ground.
• If less than the specified range, test the 5V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
• If greater than the specified range, test the 5V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM
5. Verify the scan tool AIR Pressure Sensor parameter is less than 0.5V.
• If greater than the specified range, test the signal circuit terminal 2 for a short to voltage. If the circuit tests normal, replace the ECM.
6. Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5V reference circuit terminal 1. Verify the scan tool AIR Pressure Sensor parameter is greater than 4.9V.
• If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
7. If all circuits tests normal, test or replace the AIR solenoid valve assembly.
Component Testing
Solenoid
Apply appropriately fused battery voltage and ground to the solenoid terminals and verify that the valve opens and closes completely as voltage is applied to and removed from the solenoid terminals. Observe that the valve is not obstructed or leaking.
If the valve operates incorrectly, leaks, or is obstructed, remove the obstruction or replace the AIR solenoid.
Repair Instructions
* Secondary Air Injection Check Valve Pipe Replacement (Secondary Air Injection Check Valve Pipe Replacement)
* Secondary Air Injection Pipe Replacement (Secondary Air Injection Pipe Replacement)
* Secondary Air Injection Pump Hose Replacement (Secondary Air Injection Pump Hose Replacement)
* Secondary Air Injection Pump Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for control module replacement, setup, and programming
Repair Verification
1. Engine running, observe that the AIR Pressure Sensor parameter approximately equals BARO.
2. Engine running, enable the AIR pump with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 20-25 kPa above BARO.
3. Engine running, enable the AIR system with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.