P2444
DTC P2444
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle
* Review Strategy Based Diagnosis Strategy Based Diagnosis
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions
DTC Descriptor
DTC P2444
- Secondary Air Injection System Pump Stuck ON
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.
* Secondary air injection pump is commanded ON.
* Secondary air injection diagnostic test Phase 1 and Phase 2 have run and passed.
* DTC P2444 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 greater than or less than calibrated thresholds for greater than 2 s.
Action Taken When the DTC Sets
DTC P2444 is a Type A DTC.
Conditions for Clearing the MIL/DTC
DTC P2444 is a Type A 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 P0412, P0418, 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.
Note: To prevent the secondary air injection pump from overheating, do not operate the pump consecutively for greater than 2 minutes. The pump is provided with a thermal protector that will automatically reset when allowed to cool.
3. Verify the G21 Secondary Air Injection Pump turns ON and OFF when commanding the Secondary Air Injection Pump Relay ON and OFF with a scan tool.
• If the pump does not turn ON and OFF
Refer to Circuit/System Testing
• If the pump turns ON and OFF
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
5. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing
• If the DTC does not set
6. All OK
Circuit/System Testing
1. Ignition OFF, disconnect the KR25 Secondary Air Injection Pump 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. Test or replace the KR25 Secondary Air Injection Pump Relay.
Component Testing
Relay Test
1. Ignition OFF, disconnect the KR25 Secondary Air Injection Pump Relay.
2. Test for 70-110 ohms between terminals 85-86.
• If less than 70 ohms or greater than 110 ohms
Replace the KR25 Secondary Air Injection Pump 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 KR25 Secondary Air Injection Pump 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 KR25 Secondary Air Injection Pump 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)