Diagnostic Instructions

DTC Descriptors

DTC P2430 : Secondary Air Injection (AIR) System Pressure Sensor Circuit

DTC P2431 : Secondary Air Injection System Pressure Sensor Circuit Performance

DTC P2432 : Secondary Air Injection System Pressure Sensor Circuit Low Voltage

DTC P2433 : Air Injection System Pressure Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
AIR Pressure Sensor 5-Volt Reference Voltage	P0335, P0651, P2135, P2432	P2432	P2431, P0651	P2430, P2431
AIR Pressure Sensor Signal	P2432	P2432	P2433	P2430, P2431
AIR Pressure Sensor Low Reference	--	P2433	--	P0411, P2431

Typical Scan Tool Data

AIR Pressure Sensor

Circuit	Normal Range	Short to Ground	Open	Short to Voltage
Operating Conditions: Ignition ON, Engine OFF Parameter Normal Range: BARO
AIR 5-Volt Reference Voltage	BARO	40 kPa	40 kPa	111 kPa
AIR Pressure Sensor Signal	BARO	40 kPa	40 kPa	145 kPa
AIR Low Reference	BARO	BARO	145-150 kPa	--

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. The secondary AIR injection pump provides filtered air on demand to the AIR solenoid check valve assembly. The AIR solenoid valve assembly controls the flow of air from the AIR pump to the exhaust manifold. The AIR pump relay supplies the current needed to operate the AIR pump. The AIR solenoid valve assembly has an integral check valve, pressure sensor, and solenoid. The pressure sensor monitors the air flow from the AIR pump. The engine control module (ECM) supplies the internal pressure sensor with a 5-volt reference, a low reference, and a signal circuits. The signal circuit provides the control module with a voltage relative to internal AIR pressure changes.

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 8-15 kPa above 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 15-22 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

P2431

P2432 and P2433

Conditions for Setting the DTC

P2430

P2431

P2432

The ECM determines that the AIR pressure sensor signal is less than 0.2 volt for at least 12.5 seconds.

P2433

The ECM determines that the AIR pressure sensor signal is equal to or greater than 4.7 volts for at least 12.5 seconds.

Action Taken When the DTC Sets

DTCs P2430, P2431, P2432, and P2433 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2430, P2431, P2432, and P2433 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that DTCs P0411, P0412, P0418, P0690, P2440, or P2444 are not set

⇒	If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Ignition ON, engine OFF, verify 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. If the BARO parameter is not correct for your altitude, refer to DTC P0106.

3. Engine running, command the AIR pump relay ON while observing the AIR Pressure Sensor parameter. The reading should be 15-22 kPa above the BARO reading
4. Engine running, command the AIR system ON while observing the AIR Pressure Sensor parameter. The reading should be 8-15 kPa above BARO.
5. 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

Important:  You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the AIR solenoid valve.
2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal 1 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.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 3 and ground.

⇒	If less than the specified range, test the 5-volt 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 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Verify the scan tool AIR Pressure Sensor parameter is less than 0.5 volt.

⇒	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.

5. Install a 3A fused jumper wire between the signal circuit terminal 2 and the 5-volt reference circuit terminal 3. Verify the scan tool AIR Pressure Sensor parameter is greater than 4.9 volts.

⇒	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.

6. If all circuits tests normal, replace the AIR solenoid valve assembly.

Repair Instructions

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming, or setup procedures that are required when a component or module is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 90 seconds.
5. Ignition ON, observe that the AIR Pressure Sensor parameter is within 3 kPa of the BARO parameter.
6. Engine running, command the AIR system ON with a scan tool. Observe the scan tool AIR Pressure Sensor parameter equals 8-15 kPa above BARO.
7. Engine running, command the AIR pump relay ON with a scan tool. Observe the scan tool AIR Pressure Sensor parameter equals 15-22 kPa above BARO.