P0410

CIRCUIT DESCRIPTION
The powertrain control module (PCM) activates the secondary air injection (AIR) system by grounding the AIR relay. This energizes the pump and the vacuum control solenoid. As vacuum is applied to the shut-off valve, fresh air is allowed to pass through the pump and vacuum control solenoid. The AIR pump forces fresh air past the shut-off valve and into the exhaust stream in order to accelerate catalyst operation. The PCM will run up to 3 diagnostic tests using the O2S 1 voltage and short term FT to verify system operation. The system can be diagnosed during normal AIR operation or the scan tool can activate the system specifically for diagnostic purposes. If an airflow problem is detected this, DTC will set. When inactive, the shut-off valve prevents air flow in either direction.

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0105, P0107, P0108, P0112, P0113, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0171, P0172, P0177, P0178, P0179, P0182, P0183, P0300, P0301-P0304, P0341, P0506, P0507, P0601, P0602, or P1681 are not set.
^ The AIR system is commanded ON for more than 20 seconds.
^ The intake air temperature (IAT) is between 1-151°C (32-302°F).
^ The engine coolant temperature (ECT) is between 5-114°C (41-230°F).
^ The battery voltage is more than 11.7 volts.
^ The engine run time is more than 200 seconds.
^ The calculated airflow is more than 11 g/s.
^ The accumulated flow is between 240-600 counts.
^ A fuel trim cell of 16 or 17.
^ The throttle position (TP) sensor changes less than 5 percent.
^ A stabilization time of more than 1 second.
^ The fuel ethanol composition is less than 15 percent.
^ The manifold absolute pressure (MAP) sensor is less than 30 kPa.
^ The fuel injector base pulse width is more 1.35 ms.
^ The engine speed is more than 1,150 RPM for auto transmissions.
^ The engine speed is more than 1,000 RPM for manual transmissions.

CONDITIONS FOR SETTING THE DTC
The control module detects that the O2S is less than 50 mV for 1 second during a 3-second active test, for 3 consecutive 3-second active tests.

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
An intermittent may be caused by any of the following conditions:
^ Low system airflow 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.

Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in Diagnostic Aids.

If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Diagnostic Aids.

TEST DESCRIPTION

Steps 1-8:

Steps 9-15:

Steps 16-22:

Steps 23-31:

Steps 32-43:

Steps 44-56:

Steps 57-60:

The numbers below refer to the step numbers on the diagnostic table.
16. This step checks for a restriction in the engine vacuum supply to the AIR shut-off valve.
18. This step determines if the lack of air is caused by an open in the AIR supply hose or a defective shut-off valve.