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 Connector Test Adapter Kit. Using this kit prevents damage to the component terminals and to the harness. Refer to Using Connector Test Adapters in Wiring Systems. |
AIR Pump Relay Underhood Electrical Center Terminal Identification | |||
|---|---|---|---|
Front of Vehicle | |||
Left Side of Vehicle | Ignition 1 voltage | Battery positive voltage | Right Side of Vehicle |
Pump Supply | Control | ||
| • | For an intermittent condition, refer to Intermittent Conditions . |
| • | 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
The numbers below refer to the step numbers on the diagnostic table.
-
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.
-
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.
-
This step determines if the AIR system is operating normally.
Step
| Action | values | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||||
2 | Is DTC P0412 or DTC P0418 also set? | -- | Go to Step 3 | |||||||||
3 |
Does the AIR pump turn ON and OFF with each command of the scan tool? | -- | Go to Step 18 | Go to Step 4 | ||||||||
4 | Inspect the AIR pump fuse. Is the AIR pump fuse open? | -- | Go to Step 5 | Go to Step 9 | ||||||||
5 |
Does the test lamp turn ON and OFF with each command of the scan tool? | -- | Go to Step 8 | Go to Step 6 | ||||||||
6 | Does the test lamp remain illuminated when the air pump relay is commanded ON and OFF with a scan tool? | -- | Go to Step 7 | Go to Step 34 | ||||||||
7 |
Does the test lamp remain illuminated? | -- | Go to Step 33 | Go to Step 39 | ||||||||
8 |
Does the AIR pump turn ON? | -- | Go to Intermittent Conditions | Go to Step 41 | ||||||||
9 |
Did you find and correct the condition? | -- | Go to Step 42 | Go to Step 10 | ||||||||
10 | Connect a 30-ampJ 36169-A Fused Jumper Wire between the battery positive circuit and the AIR pump supply voltage circuit at the AIR pump relay connector. Refer to Using Fused Jumper Wires in Wiring Systems. Does the AIR pump turn ON? | -- | Go to Step 16 | Go to Step 11 | ||||||||
11 | Test the battery positive voltage circuit between the AIR pump fuse and AIR pump relay for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 42 | Go to Step 12 | ||||||||
12 |
Does the test lamp illuminate? | -- | Go to Step 13 | Go to Step 35 | ||||||||
13 | Probe the ground circuit of the AIR pump harness connector with a test lamp that is connected to a battery voltage. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 14 | Go to Step 36 | ||||||||
Is the voltage drop less than the specified value? | 0.6 V | Go to Step 15 | Go to Step 35 | |||||||||
Measure the voltage drop from the AIR pump ground circuit at the AIR pump harness connector to a good ground with a DMM. Refer to Circuit Testing and Measuring Voltage Drop in Wiring Systems. Is the voltage drop less than the specified value? | 0.6 V | Go to Step 17 | Go to Step 36 | |||||||||
16 | Measure the resistance of the AIR pump relay control circuit between the powertrain control module (PCM) and the AIR pump relay with a DMM. Refer to Circuit Testing in Wiring Systems. Is the resistance less than the specified value? | 15 ohms | Go to Step 17 | Go to Step 37 | ||||||||
17 |
Important: The DMM and test leads must be calibrated to 0 ohms in order to prevent misdiagnosis. Refer to the DMM User Manual for calibration procedure.
Is the resistance within the specified range? | 1-3 ohms | Go to Step 27 | Go to Step 39 | ||||||||
Do both of the HO2S voltage parameters decrease to the specified value within 20 seconds? | 75 mV | Go to Diagnostic Aids | Go to Step 19 | |||||||||
19 |
Is a pressurized airflow present at the AIR pump shut-off valve outlet hose? | -- | Go to Step 31 | Go to Step 20 | ||||||||
20 |
Is a pressurized airflow present at the AIR pump outlet hose? | -- | Go to Step 21 | Go to Step 29 | ||||||||
21 |
Is the vacuum displayed on the gage above the specified value? | 10 in Hg (254 mm) | Go to Step 22 | Go to Step 24 | ||||||||
22 |
Does the AIR shut-off valve hold vacuum for the specified amount of time? | 30 seconds | Go to Step 23 | Go to Step 38 | ||||||||
23 | Inspect for a restriction or for a blockage in the AIR shut-off valve. Did you find and correct the condition? | -- | Go to Step 43 | Go to Step 30 | ||||||||
24 |
Is the vacuum displayed on the gage above the specified amount? | 10 in Hg (254 mm) | Go to Step 25 | Go to Step 32 | ||||||||
25 | Measure the resistance of the AIR solenoid control circuit between the PCM and the AIR solenoid with a DMM. Refer to Circuit Testing in Wiring Systems. Is the resistance less than the specified value? | 15 ohms | Go to Step 26 | Go to Step 37 | ||||||||
26 | Measure the resistance of the AIR solenoid ignition 1 voltage circuit between the ENG IGN 1 fuse and the AIR solenoid with a DMM. Refer to Circuit Testing in Wiring Systems. Is the resistance less than the specified value? | 15 ohms | Go to Step 28 | Go to Step 37 | ||||||||
27 | Test for an intermittent and for a poor connection at the AIR pump. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 42 | Go to Step 41 | ||||||||
28 | Inspect the vacuum hose between the AIR shut-off valve and AIR solenoid for a leak or restriction. Did you find and correct a condition? | -- | Go to Step 43 | Go to Step 40 | ||||||||
29 | Inspect for a restriction in one of the following components:
Did you find and correct a condition? | -- | Go to Step 43 | Go to Step 41 | ||||||||
30 | Repair the restriction or leak in the AIR shut-off valve outlet hose between the AIR shut-off valve and the crossover pipe. Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
31 |
Caution: Refer to Hot Exhaust System Caution in the Preface section. Repair the restriction in one of the following components:
Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
32 | Repair the restriction or leak in one of the following components:
Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
33 |
Did you complete the repair? | -- | Go to Step 42 | -- | ||||||||
34 |
Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
35 | Repair the open or high resistance in the AIR pump supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
36 | Repair the open or high resistance in the AIR pump ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
37 | Repair the circuit with the high resistance. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 43 | -- | ||||||||
38 | Replace the AIR shut-off valve. Refer to Secondary Air Injection Shutoff Valve Replacement . Did you complete the replacement? | -- | Go to Step 43 | -- | ||||||||
39 | Replace the AIR pump relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement? | -- | Go to Step 42 | -- | ||||||||
40 | Replace the AIR Solenoid. Refer to Secondary Air Injection Vacuum Control Solenoid Valve Replacement . Did you complete the replacement? | -- | Go to Step 43 | -- | ||||||||
41 |
Did you complete the replacement? | -- | Go to Step 42 | -- | ||||||||
42 |
Does the AIR pump relay turn ON and OFF when commanded with a scan tool? | -- | Go to Step 43 | Go to Step 2 | ||||||||
43 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 44 | ||||||||
44 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |||||||||
