P0410

DTC P0410

CIRCUIT DESCRIPTION
The Secondary Air Injection (AIR) System is designed to lower exhaust emission levels on initial start up. The AIR pump runs until closed loop is achieved.

The powertrain control module (PCM) commands the AIR pump relay and the AIR vacuum solenoid ON simultaneously by supplying a ground on the AIR pump relay control circuit and a ground to the AIR vacuum solenoid control circuit. When engine vacuum is applied to the AIR shut-off valve, airflow from the AIR pump flows through the pipes/hoses to the exhaust check valves. The air enters the exhaust stream, accelerating catalyst operation. When inactive, the exhaust check valves and the AIR shut-off valve prevent airflow in either direction.

The PCM detects a system airflow problem by monitoring the heated oxygen sensors (HO2S) during normal AIR system operation. This is a passive test. If the passive test indicates a pass, the PCM takes no further action. If the passive test fails or is inconclusive, the diagnostic will proceed with an intrusive or active test. The PCM will command the AIR system ON during closed loop operation under normal operating conditions. The active test will pass or fail based on the response from the HO2S. A lean HO2S response indicates that the secondary AIR system is functioning normally. An increasing short term fuel trim (FT) value also indicates a normally functioning system. The AIR diagnostic consists of the passive test and the active tests. The AIR diagnostic requires failure of the passive and active tests on two consecutive key cycles to illuminate the MIL and store a DTC. If the PCM detects that the HO2S and Short Term FT did not respond as expected on both of the engine banks, DTC P0410 sets.

CONDITIONS FOR RUNNING THE DTC
- DTCs P0101, P0102,P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0125, P0128, P0131, P0132, P0133, P0134, P0135, P0136, P0137, P0138, P0140, P0141, P0151, P0152, P0154, P0155, P0156, P0157, P0158, P0160, P0161, P0171, P0172, P0174, P0175, P0200, P0220, P0300, P0335, P0336, P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, P0442, P0443, P0455, P0446, P0449, P0496, P1133, P1134, P1153, P1154, P1235, P1258, P2135 are not set.
- The fuel level is more than 12.5 percent but less than 87.5 percent.
- The engine is running for more than 30 seconds.
- The mass air flow (MAF) is less than 23 g/s.
- The air fuel ratio is 14.7:1.
- The engine load is less than 40 percent.
- The ignition voltage is more than 11.7 volts.
- The vehicle speed is more than 25 km/h (15 mph).
- The engine is operating in closed loop for more than 15 seconds.
- The engine speed is more than 850 RPM.
- The engine coolant temperature (ECT) is between -10 and +110°C (+14 and +230°F).
- The intake air temperature (IAT) is between -10 and +100°C (+14 and +212°F).
- The fuel system is operating in fuel trim cells 1, 2, 3, 4 or 5.
- The short term FT is between -4 and +4 percent.
- The start-up engine coolant temp is less than 70°C (158°F).
- The engine is not operating in any of the following modes:
- Power enrichment
- Decel fuel cut-off mode
- Catalyst over temperature

CONDITIONS FOR SETTING THE DTC
- When the AIR pump is commanded ON, during closed loop Operation and the HO2S voltages do not decrease below 222 mV for 1.5 seconds.
- The short term FT does not change more than a predetermined amount.

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
- When commanding the AIR system ON with a scan tool the PCM will activate the AIR pump and the AIR solenoid. The fuel control system will then enter a open loop status. This action will allow fresh air to enter the exhaust stream and allow the HO2S 1 mV parameters to drop to near 0 mV. This would indicate a properly operating system.
- However if the AIR pump does not operate or there is no airflow from the AIR pump entering the exhaust stream due to a leak in the AIR system, the HO2S 1 mV parameter may still decrease to 100 mV. This is due to fresh air being drawn into the exhaust stream from the exhaust check valve operation and the opening of the AIR shut-off valve. The HO2S 1 will respond with a decreasing mV parameter as a result of fresh air leaning out the exhaust gases. The HO2S 1 parameter voltages may decrease to nearly 100 mV but not approach the near 0 mV parameter.
- For any test that requires probing the PCM harness connector or probing a component harness connector, use the J 35616-B Connector Test Adapter Kit. Using this kit prevents damage to the component terminals and to the harness. Refer to Using Connector Test Adapters in Diagnostic Aids.




- For an intermittent condition, refer to Intermittent Conditions. Diagnostic Strategies
- The vacuum lines at the AIR solenoid cannot be reversed, this condition may hold the shut-off valve open continually.
- Leaking exhaust check valves will leave traces of exhaust carbon and water laden exhaust gases in the AIR system and a possibility of heat damage to the AIR hoses and AIR shut-off valve.
- An intermittent may be caused by any of the following conditions:
- Low system air flow
- Excessive exhaust system back pressure
- Moisture, water or debris ingested into the AIR pump
- Pinched, kinked, heat damaged, or deteriorated hoses or vacuum hoses.
- Restrictions in the pump inlet, duct, or filter

TEST DESCRIPTION

Steps 1-10:

Steps 11-17:

Steps 18-25:

Steps 26-35:

Steps 36-44:

The numbers below refer to the step numbers on the diagnostic table.
14. This step determines if excessive resistance on the AIR pump supply circuit is the cause for an inoperative AIR pump. Two ohms of resistance on this circuit can prevent the AIR pump from running.
15. This step determines if excessive resistance on the AIR pump ground circuit is the cause for an inoperative AIR pump. Two ohms of resistance on this circuit can prevent the AIR pump from running.
18. This step determines if the AIR system is operating normally.