Circuit Description
An 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, diagnostic trouble code (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, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0151, P0152, P0153, P0154, P0155, P0157, P0158, P0160, P0161, P0171, P0172, P0174, P0175, P0200, P0300, P0335, P0336, P0351-P0358, P0442, P0443, P0446, or P0449 are not set. |
| • | The engine run time is more than 2 seconds. |
| • | The engine load is less than 40 percent. |
| • | The vehicle speed is more than 15 km/h (25 mph). |
| • | The engine air flow is less than 20 g/s. |
| • | The engine speed is more than 900 RPM. |
| • | The ignition voltage is more than 11.7 volts. |
| • | The air fuel ratio is 13.125:1. |
| • | The startup ECT is less than 70°C 176°F. |
| • | The ECT is more than 70°C (158°F), but less than 110°C (230°F). |
| • | The IAT is more than 2°C (230°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 when the AIR pump turns on during closed loop operation. |
| • | Short term fuel trim does not go above a predetermined amount when the AIR pump turns on during closed loop operation. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/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
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.
| • | Using Freeze Frame/Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame/Failure Records data can aid in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also aid determining how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the 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, refer to Symptoms - Engine Controls . |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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If DTC P0418 sets, this indicates the control side of the relay is not operating. Refer to DTC P0418 for further diagnosis. Vacuum lines that are reversed on the AIR solenoid causes this DTC to set.
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The AIR MaxiFuse® is located in the underhood electrical center.
-
The AIR pump relay is located near the AIR pump.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |||||||
|
Important: Ensure the vacuum source is on the proper side of the AIR solenoid before proceeding. The vacuum source port is on the same side as the mounting bracket. Is DTC P0418 set? | Go to DTC P0418 | Go to Step 3 | |||||||
Is the AIR MaxiFuse® OK? | Go to Step 4 | Go to Step 12 | |||||||
4 |
Does the AIR pump turn ON? | Go to Step 9 | Go to Step 5 | ||||||
Does the test lamp illuminate? | Go to Step 6 | Go to Step 19 | |||||||
6 | Jumper the B+ terminal to the AIR pump feed circuit at the relay harness connector using a fused jumper wire. Refer to Using Fused Jumper Wires in Wiring Systems. Does the AIR pump turn ON? | Go to Step 25 | Go to Step 7 | ||||||
7 |
Does the test lamp illuminate? | Go to Step 8 | Go to Step 20 | ||||||
8 |
Does the test lamp illuminate? | Go to Step 28 | Go to Step 21 | ||||||
9 | Did the AIR solenoid valve turn ON when the AIR system was enabled? | Go to Step 15 | Go to Step 10 | ||||||
10 |
Does the test lamp illuminate? | Go to Step 11 | Go to Step 23 | ||||||
11 |
Does the test lamp illuminate? | Go to Step 26 | Go to Step 21 | ||||||
12 |
Does the test lamp illuminate? | Go to Step 22 | Go to Step 13 | ||||||
13 | Probe the AIR pump and AIR solenoid feed circuit at the AIR pump relay harness connector using the test lamp connected to B+. Does the test lamp illuminate? | Go to Step 24 | Go to Step 14 | ||||||
14 |
Does the AIR MaxiFuse® open? | Go to Step 27 | Go to Step 29 | ||||||
15 |
Does an engine vacuum display on the vacuum gauge? | Go to Step 16 | Go to Step 30 | ||||||
16 |
Is an engine vacuum indicated on the vacuum gauge when the AIR pump is enabled? | Go to Step 17 | Go to Step 27 | ||||||
17 |
Is air present at the outlet of the AIR pump? | Go to Step 18 | Go to Step 33 | ||||||
18 |
Is air present at the AIR outlet hose? | Go to Step 32 | Go to Step 31 | ||||||
19 | Repair the open circuit between the fuse and the relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
20 | Repair the open circuit between the AIR pump and the AIR relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
21 | Repair the faulty ground connection or the open ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
22 | Repair the short to ground in the ignition feed circuit between the fuse and the relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
23 | Repair the open circuit in the circuit between the AIR solenoid and the AIR pump relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
24 | Repair the short to ground in the circuit between the AIR pump relay and the AIR pump and solenoid. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 34 | -- | ||||||
25 | Replace the AIR pump relay. Did you complete the replacement? | Go to Step 34 | -- | ||||||
26 |
Did you find and correct the condition? | Go to Step 34 | Go to Step 27 | ||||||
27 | Replace the AIR solenoid valve. Refer to Secondary Air Injection Solenoid Valve Replacement . Is the action complete? | Go to Step 34 | -- | ||||||
28 |
Did you find and correct the condition? | Go to Step 34 | Go to Step 29 | ||||||
29 |
Does the AIR pump MaxiFuse® open? | Go to Step 33 | Go to Diagnostic Aids | ||||||
30 |
Important: Inspect the vacuum check valve for proper installation. The tapered side of the check valve goes toward the vacuum source. Also inspect for vacuum with the check valve removed from the vacuum line. If there is vacuum, replace the check valve. Repair the vacuum source. Did you complete the repair? | Go to Step 34 | -- | ||||||
31 | Repair the restriction or for an AIR hose that is not connected at the point where the AIR system branches to both sides. Did find and correct the condition? | Go to Step 34 | -- | ||||||
32 | Replace the AIR shut-off valve. Refer to Secondary Air Injection Shut Off Valve Replacement . Did you complete the replacement? | Go to Step 34 | -- | ||||||
33 | Replace the AIR pump. Refer to Secondary Air Injection Pump Replacement . Did you complete the replacement? | Go to Step 34 | -- | ||||||
34 |
Does the DTC run and pass? | Go to Step 35 | Go to Step 2 | ||||||
35 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK | |||||||
