P2440

DTC P2440

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 P2440
- Secondary Air Injection System Shut-Off Valve Stuck Open

Circuit/System Description

The secondary air injection system aids in the reduction of hydrocarbon emissions during a cold start. The electric air pump forces fresh air into the exhaust stream in order to accelerate the catalyst operation. A pressure sensor is used to monitor the air flow from the secondary air injection pump. The engine control module (ECM) supplies voltage to the 5-volt reference circuit and supplies a ground to the low reference circuit. The sensor provides a signal voltage to the ECM relative to the pressure changes within the secondary air injection system.

Ignition voltage is supplied to the secondary air injection pump and air injection shutoff/check valve relay. The ECM controls the relay by grounding the control circuit, which activates the relay. When the relay contact closes, voltage is supplied to the pump and the valve, which turns the pump on and opens the valve.

The diagnostic uses 3 phases to test the secondary air injection system:

* DTCs P0411 and P2430 run during Phase 1

* DTCs P2430 and P2440 run during Phase 2

* DTC P2444 runs during Phase 3

During phase 1, both the secondary air injection pump and the secondary air injection shutoff and check valve is activated. Normal secondary air function occurs. Expected system pressure is 6-14 kPa (0.9-2.0 psi) above BARO.

During phase 2, only the secondary air injection pump is activated. The shutoff and check valve is closed. Pressure sensor performance and shutoff and check valve deactivation are tested. Expected system pressure is 18-28 kPa (2.6-4.0 psi) above BARO.

During phase 3, neither the secondary air injection pump nor the secondary air injection shutoff and check valve is activated. Secondary air injection pump deactivation is tested. Expected system pressure equals BARO.

Conditions for Running the DTC

* DTC P0101-P0103, P0106-P0108, P0111-P0114, P0116-P0118, P0121-P0123, P0128, P0201-P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300-P0304, P0351-P0354, P0412, P0418, P0420, P0606, P0641, P0651, or P2430-P2433 is not set.

* The engine has been OFF for greater than 10 s.

* The ignition voltage is greater than 10 V.

* The engine speed is less than 3,000 RPM.

* The intake air temperature (IAT) is greater than -12°C (+10°F).

* The engine coolant temperature (ECT) is between -12 and +38°C (10-100°F).

* The barometric pressure (BARO) is greater than 60 kPa (8.7 psi).

* The manifold absolute pressure (MAP) sensor is greater than 20 kPa (2.9 psi).

* The mass air flow (MAF) is less than 50 g/s.

* The secondary air injection pump is commanded ON.

* DTC P2440 runs once per ignition cycle when the above conditions are met for greater than 3 s.

Conditions for Setting the DTC

The ECM detects that average difference between the predicted system pressure and the actual system pressure is less than a calibrated threshold for greater than 1.5 s.

Action Taken When the DTC Sets

DTC P2440 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2440 is a Type B DTC.

Diagnostic Aids

Ice buildup due to condensation/water in the air passages or pump may cause this DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1

Description and Operation

Secondary Air Injection System Description Description and Operation

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 Programming and Relearning for scan tool information

Circuit/System Verification

1. Vehicle in Service Mode,

2. Verify that DTC P0411, P0412, P0418, P2430, P2431, P2432, or P2433 is not set.

• If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• If none of the DTCs are set.

3. Verify the scan tool BARO pressure parameter is within the range specified in the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.

• If not within the specified range
Refer to DTC P0106 P0106 for further diagnosis.

• If within the specified range

4. Verify the scan tool Secondary Air Injection Pressure Sensor parameter and the BARO pressure parameter are within 3 kPa (0.4 psi).

• If not within the specified range
Replace the Q29 secondary air injection solenoid valve.

• If within the specified range

5. Engine running

Note: Engine coolant temperature must be greater than 5°C (41°F) to enable scan tool device control.

6. Command the Secondary Air Injection Pump Relay ON with a scan tool. Verify the scan tool Secondary Air Injection Pressure Sensor parameter increases between 18-28 kPa (2.6-4.0 psi).

• If not within the specified range
Refer to Circuit/System Testing

• If within the specified range

7. 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.

• If the DTC sets
Refer to Circuit/System Testing

• If the DTC does not set

8. All OK

Circuit/System Testing

1. Vehicle OFF, disconnect the KR26 secondary air injection solenoid valve relay. Vehicle in Service Mode.

2. Verify a test lamp does not illuminate between the control circuit terminal 87 and ground.

• If the test lamp illuminates
Repair the short to voltage on the circuit.

• If the test lamp does not illuminate

3. Vehicle OFF, connect the KR26 secondary air injection solenoid valve relay.

4. Disconnect the harness connector at the Q29 secondary air injection solenoid valve. Vehicle in Service Mode.

5. Verify a test lamp does not illuminate between the control circuit terminal 5 and ground.

• If the test lamp illuminates
Test or replace the KR26 secondary air injection solenoid valve relay.

• If the test lamp does not illuminate

6. Verify the following conditions do not exist:

* Hoses/pipes restricted or blocked upstream of valve

* Hoses/pipes leaking or disconnected

* Damaged or restricted secondary air injection pump

* Damaged secondary air injection check valve

• If a condition is located
Repair or replace the affected component as necessary.

• If all components test normal

7. Vehicle OFF, remove the Q29 secondary air injection solenoid valve.

8. Connect the harness connector at the Q29 secondary air injection solenoid valve.

9. Connect the secondary air injection pipe to the Q29 secondary air injection solenoid valve.

10. Vehicle in service mode, command the Secondary Air Injection Pump Relay ON with a scan tool. Verify there is NO airflow through the Q29 secondary air injection solenoid valve.

• If airflow
Replace the Q29 secondary air injection solenoid valve.

• If no airflow

11. Replace the G21 secondary air injection pump.

Component Testing

Relay Test

1. Vehicle OFF, disconnect the KR26 secondary air injection solenoid valve relay.

2. Test for 70-110 ohms between terminals 85-86.

• If not within the specified range
Replace the relay.

• If within the specified range

3. Test for infinite resistance between the terminals listed below:

* 30 and 86

* 30 and 87

* 30 and 85

* 85 and 87

• If less than infinite resistance
Replace the relay.

• If infinite resistance

4. Install a 15 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.

5. Test for less than 2 ohms between terminals 30 and 87.

• If 2 ohms or greater
Replace the relay.

• If less than 2 ohms

6. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Secondary Air Injection Check Valve Replacement Service and Repair for secondary air injection solenoid valve replacement.