Circuit Description
A secondary air injection (AIR) pump is used on this vehicle to lower tail 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 . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step will determine if the PCM is capable of controlling the AIR pump relay.
-
This step will determine if the AIR system is functioning correctly.
-
The engine must be running for this test to ensure a vacuum supply to the AIR system.
-
This step tests for a short to voltage on the control circuit.
-
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.
-
This step determines if the AIR pump is capable of producing airflow.
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 | Turn ON the ignition , with the engine OFF. Does the secondary air injection (AIR) pump run constantly? | -- | Go to Step 25 | Go to Step 3 | ||||||||||||||
3 |
Is the long term fuel trim above the specified amount? | 10% | Go to Step 14 | Go to Step 4 | ||||||||||||||
Does the AIR pump turn ON and OFF? | -- | Go to Step 5 | Go to Step 6 | |||||||||||||||
Do the HO2S 1 bank 1 and HO2S 1 bank 2 decrease to the specified value within 6 seconds? | 100 mV in 6 seconds. | Go to Diagnostic Aids | Go to Step 15 | |||||||||||||||
6 |
Does the test lamp turn ON and OFF? | -- | Go to Step 11 | Go to Step 7 | ||||||||||||||
7 |
Is the AIR fuse open? | -- | Go to Step 28 | Go to Step 8 | ||||||||||||||
8 | Connect the battery cables. Probe the AIR pump relay battery positive voltage circuit, switched side , at the fuse block with a test lamp connected to a good ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 9 | Go to Step 40 | ||||||||||||||
9 | Turn the ignition to the ON position. Probe the AIR pump relay ignition 1 voltage circuit, coil side , at the fuse block with a test lamp connected to a good ground. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 10 | Go to Step 41 | ||||||||||||||
10 | Probe the AIR pump relay control circuit, at the fuse block with a test lamp connected to battery voltage. Refer to Probing Electrical Connectors in Wiring Systems. Command the AIR pump relay ON and OFF. Does the test lamp turn ON and OFF? | -- | Go to Step 12 | Go to Step 30 | ||||||||||||||
11 | Probe the AIR pump ground circuit of the AIR pump with a test lamp connected to battery voltage. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 37 | Go to Step 45 | ||||||||||||||
12 |
Does the AIR pump turn ON? | -- | Go to Step 36 | Go to Step 13 | ||||||||||||||
13 | Test for an open or a high resistance in the AIR pump battery supply voltage circuit between the AIR relay and the AIR pump with a DMM. Is the resistance within the specified range? | 0-5 ohms. | Go to Step 37 | Go to Step 43 | ||||||||||||||
14 | Run the engine at 1500 RPM for 1 minute. Is the long term fuel trim above the specified amount? | 10% | Go to Fuel System Diagnosis | Go to Step 15 | ||||||||||||||
15 |
Does the AIR shut-off valve hold vacuum for the specified amount? | 30 seconds. | Go to Step 16 | Go to Step 49 | ||||||||||||||
Is the vacuum displayed on the gage at the specified value? | 0 in Hg | Go to Step 17 | Go to Step 50 | |||||||||||||||
17 |
Does the vacuum displayed on the gage increase to above the specified amount and drop back to zero inches? | 10 in Hg | Go to Step 31 | Go to Step 18 | ||||||||||||||
18 |
Does the vacuum displayed on the gage increase to above specified amount and drop back to zero inches? | 10 in Hg | Go to Step 47 | Go to Step 19 | ||||||||||||||
19 |
Is the vacuum displayed on the gage above the specified amount? | 10 in Hg | Go to Step 21 | Go to Step 20 | ||||||||||||||
20 |
Is the vacuum displayed on the gage above the specified amount? | 10 in Hg | Go to Step 34 | Go to Intake Manifold Cleaning and Inspection in Engine Mechanical-4.3L Unit Repair | ||||||||||||||
21 |
Does the test lamp turn ON and OFF? | -- | Go to Step 22 | Go to Step 23 | ||||||||||||||
22 | Probe the AIR control solenoid ground circuit of the AIR solenoid with a test lamp connected to battery voltage. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 38 | Go to Step 45 | ||||||||||||||
23 | Is the AIR control solenoid fuse open? | -- | Go to Step 42 | Go to Step 24 | ||||||||||||||
24 | Test the AIR solenoid supply voltage circuit for an open or high resistance and repair as necessary. Refer to Circuit Testing and Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | -- | ||||||||||||||
Does the secondary air injection (AIR) pump run constantly? | -- | Go to Step 26 | Go to Step 27 | |||||||||||||||
26 |
Does the test lamp illuminate? | -- | Go to Step 44 | Go to Diagnostic Aids | ||||||||||||||
27 | Probe the AIR pump relay control circuit at the fuse block with a test lamp connected to battery voltage. Refer to Probing Electrical Connectors in Wiring Systems. Does the test lamp illuminate? | -- | Go to Step 46 | Go to Step 48 | ||||||||||||||
28 |
Did you find and correct the condition? | -- | Go to Step 53 | Go to Step 29 | ||||||||||||||
Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 51 | |||||||||||||||
Test the AIR pump relay control circuit for an open or short to voltage. Refer to Wiring Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 39 | |||||||||||||||
31 |
Does air pressure flow at the crossover hose? | -- | Go to Step 34 | Go to Step 32 | ||||||||||||||
32 |
Does air pressure flow at the shut-off valve? | -- | Go to Step 34 | Go to Step 33 | ||||||||||||||
33 |
Does air pressure flow at the pump outlet? | -- | Go to Step 34 | Go to Step 35 | ||||||||||||||
34 | Inspect for leaks or restrictions on the following components:
Did you find and correct a condition? | -- | Go to Step 47 | Go to Step 35 | ||||||||||||||
35 | Inspect the AIR inlet and outlet hoses for leaks or restrictions. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 51 | ||||||||||||||
36 | Inspect for poor connections at the AIR pump relay block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 48 | ||||||||||||||
37 | Inspect for poor connections at the AIR pump electrical connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 51 | ||||||||||||||
38 | Inspect for poor connections at the AIR vacuum control solenoid electrical connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 50 | ||||||||||||||
39 | Inspect for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct a condition? | -- | Go to Step 53 | Go to Step 52 | ||||||||||||||
40 | Repair the open or short to ground in the battery positive voltage circuit to the AIR pump relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | -- | ||||||||||||||
41 | Repair the open or short to ground in the ignition 1 voltage circuit to the AIR pump relay. Replace fuse E, as necessary. Refer to Wiring Repairs in Wiring Systems. Did you find and complete a condition? | -- | Go to Step 53 | Go to Step 48 | ||||||||||||||
42 | Repair the short to ground in the AIR solenoid supply voltage circuit and replaced the AIR solenoid fuse as necessary. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | -- | ||||||||||||||
43 | Repair the open or the high resistance or short to ground in the AIR pump supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | -- | ||||||||||||||
44 | Repair the short to voltage in the AIR pump supply voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | -- | ||||||||||||||
45 | Repair the open or high resistance in the AIR ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | -- | ||||||||||||||
46 | Repair the short to ground in the AIR pump relay control circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 53 | Go to Step 52 | ||||||||||||||
47 | Replace the hoses or components, as necessary. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement - Bank 1 and Secondary Air Injection Check Valve and Check Valve Pipe Replacement - Bank 2 . Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
48 | Replace the AIR pump relay. Refer to Electrical Center Identification Views in Wiring Systems. Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
49 | Replace the AIR shut off valve. Refer to Secondary Air Injection Shut Off Valve Replacement . Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
50 | Replace the AIR vacuum control solenoid. Refer to Secondary Air Injection Solenoid Valve Replacement . Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
51 | Replace the AIR pump. Refer to Secondary Air Injection Pump Replacement . Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
52 |
Important: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement . Did you complete the replacement? | -- | Go to Step 53 | -- | ||||||||||||||
53 |
Does the DTC run and pass? | -- | Go to Step 54 | -- | ||||||||||||||
54 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |||||||||||||||
