P0410

CIRCUIT DESCRIPTION
A secondary air injection (AIR) pump is used on this vehicle to lower fail pipe emissions on start-up. The powertrain control module (PCM) supplies a ground to the AIR pump relay, which energizes the AIR pump and the AIR solenoid valve. Engine vacuum is applied to the AIR shut-off valve when the AIR solenoid is energized. The engine vacuum opens the AIR shut-off valve which allows AIR to flow to the exhaust manifolds.

The PCM monitors the heated oxygen sensor (HO2S) voltages to diagnose the AIR system. During the AIR test, the PCM activates the AIR pump during Closed Loop operation. When the AIR system is activated, the PCM monitors the HO2S voltages and short term fuel trim values for both banks of the engine. If the AIR system is operating properly, the HO2S voltages should go low and the short term fuel trim should go high. If the PCM determines that the HO2S voltages for both banks did not respond as expected during the tests, DTC P0410 sets. If only one sensor responded, the PCM sets either a DTC P1415 or DTC P1416 to indicate on which bank the AIR system is inoperative.

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0157, P0158, P0160, P0161, P0171, P0172, P0174, P0175, P0200, P0300, P0440, P0442, P0446, P0506, P0507 are not set.
^ The engine run time is more than 15 seconds after Closed Loop operation.
^ The engine load is less than 33 percent.
^ The engine air flow is less than 20 g/s.
^ The engine speed is more than 750 RPM.
^ The ignition voltage is more than 11.7 volts.
^ The air/fuel ratio is equal to 14.7:1.
^ The engine coolant temperature (ECT) is between 2-110°C (36-230°F).
^ A fuel trim cell of 4 or 5.
^ The intake air temperature (IAT) is between 20-100°C (68-212°F).
^ The fuel system is not operating in power enrichment or deceleration fuel cut-off (DFCO).
^ The short term fuel trim is +3 to -3 percent.
^ The start-up ECT is below 80°C (176°F).
^ The vehicle speed is less than 15 km/h (25 mph).
^ The HO2S voltage remains above 222 mV for more than 2 seconds.

CONDITIONS FOR SETTING THE DTC
^ The HO2S voltage remains 222 mV for more than 4 seconds.
^ The short term fuel trim does not increase by 6 percent for each bank when the AIR pump is active during Closed Loop.

ACTION TAKEN WHEN THE DTC SETS
^ The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
^ The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
^ A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
^ A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
^ Clear the MIL and the DTC with a scan tool.

DIAGNOSTIC AIDS
^ Inspect for the following conditions:
- Low system air flow may cause this DTC to set.
- Excessive exhaust system back pressure
- Moisture, water, or debris ingested into the AIR pump
- Pinched, kinked, heat damaged, or deteriorated hoses or vacuum lines
- Restrictions in the pump inlet, duct, or filter
- An air pump that has become inoperative and showing signs of exhaust gases in the outlet port would indicate a check valve failure.
^ The system will go lean if an injector is not suppling enough fuel.
^ A lean condition could be present during high fuel demand.
^ Review Failure Records with a scan tool. If an intermittent condition is suspected, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-8:

Steps 9-19:

Steps 20-31:

Steps 32-43:

Steps 44-54:

The numbers below refer to the step numbers on the diagnostic table.
4. This step will determine if the PCM is capable of controlling the AIR pump relay.
5. This step will determine if the AIR system is functioning correctly.
16. The engine must be running for this test to ensure a vacuum supply to the AIR system.
25. This step tests for a short to voltage on the control circuit.
29. An open fuse for the battery feed circuit could be caused by a short to ground in the components operated by the relay. Inspect the wiring in the circuits on the switched side of the relay. Refer to Diagnostic Aids.
30. This step determines if the AIR pump is capable of producing airflow.