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 Cut-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 in the shutoff/check valve 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 relays. The ECM controls the relays by grounding the control circuits, which activates the relays. When the relay contacts close, 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, the secondary air injection pump and the secondary air injection shutoff and check valve are activated. Normal secondary air function occurs. Expected system pressure is 5-13 kPa (0.7-1.9 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 14-25 kPa (2.0-3.6 psi) above BARO.
During phase 3, neither the secondary air injection pump nor the secondary air injection shutoff and check valve are activated. Secondary air injection pump deactivation is tested. Expected system pressure equals BARO.
Conditions for Running the DTC
* DTC P0101, P0102, P0103, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0128, P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P0351, P0352, P0353, P0354, P0412, P0418, P0420, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157, P2227, P2228, P2229, P2230, P2430, P2431, P2432, or P2433 is not set.
* Greater than 30 min has elapsed since the last cold start.
* The ignition voltage is between 10-32 V.
* The engine speed is less than 5,000 RPM.
* The intake air temperature (IAT) is greater than -11°C (12.2°F).
* The engine coolant temperature (ECT) is between -11 and +56°C (12.2-133°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.
* Secondary air injection diagnostic test Phase 1 has run and passed.
* 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 the secondary air 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 DTC
DTC P2440 is a Type B DTC.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
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 Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
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.
• 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 P2227-P2230 P2227.
• 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
6. Verify the scan tool Secondary Air Injection Pressure Sensor parameter increases between 14-25 kPa (2.0-3.6 psi) when the Secondary Air Injection Pump Relay is commanded ON with a scan tool.
• 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. Ignition OFF, disconnect the KR26 Secondary Air Injection Solenoid Valve Relay. Ignition ON.
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. Ignition OFF, connect the KR26 Secondary Air Injection Solenoid Valve Relay.
4. Disconnect the harness connector at the Q29 Secondary Air Injection Solenoid Valve. Ignition ON.
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 conditions listed below 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 exists
Repair or replace the affected component as necessary.
• If none of the conditions exist
7. Ignition 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. Ignition ON, command the Secondary Air Injection Pump Relay ON with a scan tool. Verify there is NO airflow through the 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. Ignition OFF, disconnect the KR26 Secondary Air Injection Solenoid Valve Relay.
2. Test for 70-110 ohms between terminals 85-86.
• If less than 70 ohms or greater than 110 ohms
Replace the KR26 Secondary Air Injection Solenoid Valve Relay.
• If between 70-110 ohms
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 KR26 Secondary Air Injection Solenoid Valve 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 KR26 Secondary Air Injection Solenoid Valve Relay.
• If less than 2 ohms
6. All OK
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Relay Replacement (Within an Electrical Center) Relay Replacement (Within an Electrical Center)Relay Replacement (Attached to Wire Harness) Relay Replacement (Attached to Wire Harness)
* Secondary Air Injection Pump Replacement Service and Repair
* Secondary Air Injection Check Valve Replacement Service and Repair for secondary air injection solenoid valve replacement
* Secondary Air Injection Pump Pipe Replacement Secondary Air Injection Pump Pipe Replacement