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For 1990-2009 cars only

DTC P2430 L26, NU3

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    •  Strategy Based Diagnosis

DTC Descriptor

DTC P2430 : Secondary Air Injection (AIR) System Pressure Sensor Stuck in Range

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Pressure Sensor 5-Volt Reference Voltage

P2432

P2432

P2431

P2430, P2431

Pressure Sensor Signal

P2432

P2432

P2433

P2430, P2431

Pressure Sensor Low Reference

--

P2433

--

--

Pump Voltage Supply

P0411

P0411

P2444

--

Pump Ground

--

P0411

--

--

Solenoid Voltage Supply

P0411

P0411

P2440

--

Solenoid Ground

--

P0411

--

--

Pump Relay Coil Voltage Supply

P0411, P0418

P0411, P0418

--

--

Pump Relay Coil Control

P0418, P2444

P0411, P0418

P0418

--

Pump Relay Switch Supply

P0411

P0411

--

--

Solenoid Relay Coil Voltage Supply

P0411, P0412

P0411, P0412

--

--

Solenoid Relay Coil Control

P0412, P2440

P0411, P0412

P0412

--

Solenoid Relay Switch Supply

P0411

P0411

--

--

Typical Scan Tool Data

AIR Pressure Sensor

Circuit

Normal Range

Short to Ground

Open

Short to Voltage

Operating Conditions: Key ON, Engine OFF

5-Volt Reference Voltage

BARO

41 kPa

41 kPa

111 kPa

Pressure Sensor Signal

BARO

42 kPa

41 kPa

150 kPa

Low Reference

BARO

BARO

145 kPa

BARO

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 valve 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 powertrain control module (PCM) supplies the internal pressure sensor with a 5-volt 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 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 15-20 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 PCM 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

    • DTCs P0412, P0418, P0606, P0641, P0651, P2432, P2433 are not set.
    • The AIR pump is commanded ON.
    • The start-up engine coolant temperature (ECT) is between 5-50°C (41-122°F).
    • The start-up intake air temperature (IAT) is between 5-60°C (41-140°F).
    • DTC P2430 runs continuously when the above conditions are met.

Conditions for Setting the DTC

    • The measured AIR pressure change does not meet expected pressure changes during AIR pump phase 1 or phase 2 operation.
    • DTC P2430 sets within 8 seconds when the above condition is met.

Action Taken When the DTC Sets

DTC P2430 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2430 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Controls Connector End Views
    •  Powertrain Control Module Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

    •  Diagnostic Trouble Code (DTC) Type Definitions
    •  Diagnostic Trouble Code (DTC) Types

Scan Tool Reference

    •  Scan Tool Data Definitions
    •  Scan Tool Data List
    •  Scan Tool Output Controls

Circuit/System Verification

    • Ignition ON, verify that the AIR pump is not activated.
    • Ignition ON, observe that the AIR Pressure Sensor parameter approximately equals BARO.
       ⇒If not equal, verify that the BARO reading is correct for your altitude. Refer to Altitude Versus Barometric Pressure . If the reading is not correct for your altitude, diagnose the MAP sensor. Refer to Manifold Absolute Pressure Sensor Diagnosis
    • Engine running, enable the AIR solenoid with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.
       ⇒If less than the specified range, verify that the AIR pump is activating. If AIR pump activation is normal, inspect the hoses/pipes between the pump and the AIR solenoid valve for leaks and obstructions.

Circuit/System Testing

    Important: Circuit/System Verification MUST be performed first or misdiagnosis may result.

  1. Ignition OFF, disconnect the harness connector at the AIR solenoid valve.
  2. Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PCM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal and ground.
  5. 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 PCM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the PCM.
  6. Verify the scan tool AIR Pressure Sensor parameter is less than 0.5 volts.
  7. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the PCM.
  8. Install a 3A fused jumper wire between the signal circuit terminal and the 5-volt reference circuit terminal. Verify the scan tool AIR Pressure Sensor parameter is greater than 4.9 volts.
  9. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the PCM.
  10. Ignition OFF, connect all electrical connectors.
  11. Engine RUNNING, enable the AIR solenoid valve with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.
  12. If not within the specified range, continue with this procedure.
  13. Remove the AIR inlet hose from the AIR pump.
  14. Engine RUNNING, enable the AIR solenoid valve with a scan tool and observe that the AIR Pressure Sensor Parameter increases to 8-10 kPa above BARO.
  15. If within the specified range, the AIR pump inlet hoses/pipes are restricted. Remove the restriction or replace the hose/pipe.
    If not within the specified range, continue with this procedure.
  16. Disconnect the hose from the AIR pump outlet.
  17. Disconnect the hose from the AIR solenoid valve inlet.
  18. Install a length of standard 1 inch I.D. (25.4mm) hose from the AIR pump outlet to the AIR solenoid valve inlet.
  19. Engine RUNNING, enable the AIR solenoid valve with a scan tool and observe that the AIR Pressure Sensor Parameter increases to 8-10 kPa above BARO.
  20. If within the specified range, the AIR pump outlet hoses/pipes are restricted or leaking. Remove the restriction or replace the hose/pipe.
    If less than the specified range, replace the AIR pump.
    If more than the specified range, continue with this procedure.
  21. Remove the AIR solenoid valve.
  22. Leave the standard hose and harness connector connected.
  23. Engine RUNNING, enable the AIR solenoid valve with a scan tool and observe that the AIR Pressure Sensor Parameter increases to approximately 7 kPa above BARO.
  24. If more than the specified range, replace the AIR solenoid valve.
    If within the specified range, the exhaust system is restricted. Remove the restriction or replace the appropriate component.

Component Testing

Relay Test

  1. Test between the normally-closed switch terminals, if any, for 0 ohms.
  2. Test between the normally-open switch terminals for infinite ohms.
  3. Test between each switch terminal and either coil terminal for infinite ohms.
  4. Connect the relay coil terminals to ground and fused power to energize the relay.
  5. Test between each switch terminal and each coil terminal for 0 volts.
  6. Test between the normally-closed switch terminals, if any, for infinite ohms.
  7. Test between the normally-open switch terminals for 0 ohms.

Pump

  1. Connect the AIR pump to fused battery voltage and ground and observe pressurized airflow at the pump outlet.
  2. If pressurized airflow is not observed, replace the pump.

Solenoid Valve

  1. 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.
  2. If the valve operates incorrectly, leaks, or is obstructed, remove the obstruction or replace the AIR solenoid.

Repair Instructions

    •  Secondary Air Injection Pump Replacement
    •  Secondary Air Injection Shut-Off Valve Outlet Pipe/Hose Replacement
    •  Secondary Air Injection Shutoff Valve Replacement
    •  Powertrain Control Module Replacement for control module replacement and programming

Repair Verification

  1. With the ignition ON and the engine OFF, observe that the AIR pump is not operating, and that the AIR pressure sensor parameter is approximately equal to BARO.
  2. With the engine running, enable the AIR pump with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 15-20 kPa above BARO.
  3. With the engine running, enable the AIR solenoid with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.