Circuit Description
An AIR pump is used on this vehicle to lower tail pipe emissions on start-up. The 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 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 P1416 to indicate on which bank the AIR system is inoperative.
Conditions for Running the DTC
| • | DTCs P0101, P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0131-P0161, P0171-P0175, P0200, P0300, P0335, P0336, P0351-P0358, P0506, P0507, P1220, P1221, P1258, not set. |
| • | The engine run time is greater than 2 seconds. |
| • | The TP sensor angle is not moving more than 1%. |
| • | The engine load is less than 43%. |
| • | The engine air flow is less than 22 g/s. |
| • | Engine speed is greater than 900 RPM. |
| • | The ignition voltage is greater than 11.7 volts. |
| • | The air fuel ratio is 14.7:1. |
| • | The ECT is greater than 2°C (36°F), but less than 110°C (230°F). |
| • | The IAT is greater than 2°C (36°F). |
| • | The fuel system is not operating in power enrichment or deceleration fuel cut-off. |
| • | The short term fuel trim is in cells 5 or 6. |
Conditions for Setting the DTC
| • | The HO2S voltage does not go below 222 mV within 1.2 seconds. |
| • | Short term fuel trim does not go above a predetermined amount. |
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A last test failed, or current DTC, clears when the diagnostic runs and does not fail. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Use a scan tool in order to clear the MIL and the DTC. |
Diagnostic Aids
Important: Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
| • | Casting flash in the exhaust manifold may restrict the amount of air flow necessary to affect the HO2S voltage. If you suspect this, remove the air pipe from the manifold and inspect the passage. |
| • | Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed. |
| • | For an intermittent condition, refer to Symptoms . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Value(s) | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||||||||||
2 |
Important: Before proceeding with this diagnostic table ensure that the AIR pump is operating and that air is present at the outlet of the AIR shut-off valve. If the AIR pump is inoperative and/or no air is present at the outlet of the AIR shut off valve, refer to DTC P0410 Secondary Air Injection (AIR) System for further diagnosis.
Does the HO2S voltage drop below the specified value? | 350 mV | Go to Diagnostic Aids | |||||||||
Visually/physically inspect all hoses and pipes for:
Are all of the above OK? | -- | |||||||||||
4 |
Is air present at the hose outlet? | -- | ||||||||||
5 | Repair the restriction or blockage in AIR hoses/pipes between the left exhaust manifold and the point where the system branches to both sides of the engine. Is the action complete? | -- | -- | |||||||||
6 | Repair the condition found. Is the action complete? | -- | -- | |||||||||
7 | Replace the check valve. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement - Bank 1 . Is the action complete? | -- | -- | |||||||||
8 |
Does the scan tool indicate that this test ran and passed? | -- | ||||||||||
9 | Select the Capture Info option and the Review Info option using the scan tool. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to the applicable DTC table | System OK |
