Circuit Description
An secondary air injection system (AIR) pump is used on this vehicle in order to lower tail pipe emissions at start-up. The vehicle control module (VCM) supplies a ground to the AIR pump relay, which energizes the AIR pump and the AIR solenoid.
When the AIR pump is enabled, the VCM monitors the heated oxygen sensor (HO2S) voltage. If the HO2S voltages go below a calibrated threshold value, the VCM interprets this as an indication that the AIR system is operational.
When the AIR pump is disabled, the VCM monitors the HO2S voltages. The HO2S voltages should increase above a calibrated threshold value and should switch normally.
If the VCM did not sense more than a predetermined amount of HO2S rich switches, a malfunction will be reported.
The VCM will activate the AIR pump during Closed Loop operation. When the AIR system is activated, the VCM will monitor the HO2S voltages and the 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.
The VCM checks that the HO2S voltages return to above a rich threshold when the AIR pump is disabled.
If the VCM determines that the HO2S voltages for both banks did not respond as expected during the tests, DTC P0410 will set. If only one sensor responded, the VCM will set either a DT P1415 or a DTC P1416 to indicate on which bank the AIR system is inoperative.
Conditions for Running the DTC
| • | No mass air flow (MAF) DTCs |
| • | No manifold absolute pressure (MAP) DTCs |
| • | No intake air temperature (IAT) DTCs |
| • | No engine coolant temperature (ECT) DTCs |
| • | No throttle position (TP) sensor DTCs |
| • | No HO2S DTCs |
| • | No vehicle speed sensor (VSS) DTCs |
| • | No system voltage DTCs |
| • | No fuel trim DTCs |
| • | No misfire DTCs |
| • | No CCP DTCs |
| • | The MAF is less than 25 grams per second. |
| • | The engine load is less than 34 percent. |
| • | The Power Enrichment Mode is not active. |
| • | The Decel Fuel Cutoff Mode (DFCO) is not active. |
| • | The convertor over temperature is not active. |
| • | The engine run time after Closed Loop is more than 20 seconds. |
| • | The air/fuel ratio is 14.7:1. |
| • | The fuel trim counts are between 124-132. |
| • | The engine speed is above 550 RPM. |
| • | The ECT is between 80-107°C (176-225°F). |
| • | The system voltage is more than 11.7 volts. |
| • | The IAT is more than 2°C (36°F). |
Conditions for Setting the DTC
HO2S voltage is more than .222 volt (222 mV) for more than 1 second when AIR pump is enabled
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) if a failure is detected during 2 consecutive key cycles. |
| • | The control module sets the DTC and records the operating conditions at the time the diagnostic failed. The failure information is stored in the scan tool Freeze Frame/Failure Records. |
Conditions for Clearing the MIL or DTC
| • | The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed. |
| • | A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle. |
| • | Use a scan tool in order to clear the DTCs. |
Diagnostic Aids
Low AIR system volume may cause a DTC P1415, DTC P1416, or an intermittent complaint. Also check for the following conditions:
| • | Pinched, kinked, or restricted AIR pipes, hoses, or fittings |
| • | Leaks, holes, loose fittings, or hoses |
| • | A restricted or obstructed AIR pump inlet |
| • | Leaks or restrictions in the vacuum hoses for the AIR shut off valve. |
An AIR supply hose that is melted before the check valve could indicate exhaust gas back-flow past the check valve.
An intermittent may be caused by any of the following conditions:
| • | A poor connection |
| • | Rubbed through wire insulation |
| • | A broken wire inside the insulation |
Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step will determine if the AIR system is functioning correctly.
-
This step will determine if the VCM is capable of controlling the AIR pump relay.
-
This step is to check for a short to voltage on the control circuit.
-
The engine must be running for this test in order to ensure a vacuum supply to the system.
-
This step will determine if the AIR pump is capable of producing airflow.
-
An open fuse for the battery feed circuit could be caused by a short to ground in the components operated by the relay. Also check the wiring in the circuits on the switched side of the relay. Refer to Diagnostic Aids.
Step | Action | Value(s) | Yes | No | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | |||||||||||||
Does the short term fuel trim indicate a change of more than the specified value within 30 seconds? | 20% | Go to Step 3 | Go to Step 4 | |||||||||||||
3 | The DTC is intermittent. Are any additional DTCs stored? | -- | Go to the applicable DTC table | Go to Diagnostic Aids | ||||||||||||
4 |
Is the AIR pump running? | -- | Go to Step 16 | Go to Step 5 | ||||||||||||
5 |
Did you find a problem? | -- | Go to Step 27 | Go to Step 6 | ||||||||||||
6 |
Is the test lamp ON? | -- | Go to Step 7 | Go to Step 8 | ||||||||||||
7 | Probe the terminal for the AIR pump ground circuit on the engine harness side of the AIR pump harness connector with a test lamp connected to B+. Is the test lamp ON? | -- | Go to Step 38 | Go to Step 28 | ||||||||||||
8 |
Did you find a problem? | -- | Go to Step 27 | Go to Step 9 | ||||||||||||
9 | Check for an open in the AIR pump battery positive voltage circuit between the AIR relay and the AIR pump. Did you find a problem? | -- | Go to Step 27 | Go to Step 10 | ||||||||||||
10 | Probe the terminal for the battery positive voltage circuit at the AIR pump relay connector with a test lamp connected to a ground. Is the test lamp ON? | -- | Go to Step 11 | Go to Step 29 | ||||||||||||
11 |
Is the test lamp ON? | -- | Go to Step 12 | Go to Step 30 | ||||||||||||
Is the test lamp ON? | -- | Go to Step 35 | Go to Step 13 | |||||||||||||
13 |
Did you find a problem? | -- | Go to Step 27 | Go to Step 14 | ||||||||||||
14 | Check for an open in the AIR pump relay control circuit between the relay and the VCM. Did you find a problem? | -- | Go to Step 27 | Go to Step 15 | ||||||||||||
Is the test lamp ON? | -- | Go to Step 31 | Go to Step 39 | |||||||||||||
Does air flow from the AIR shut off valve? | -- | Go to Step 24 | Go to Step 17 | |||||||||||||
Does air flow from the hose? | -- | Go to Step 18 | Go to Step 25 | |||||||||||||
18 |
Is the vacuum above the specified value while the AIR pump is running? | 10 in. Hg | Go to Step 36 | Go to Step 19 | ||||||||||||
19 | Check for a leak or a restriction in the vacuum hose between the AIR solenoid and the AIR shut off valve. Did you find a problem? | -- | Go to Step 34 | Go to Step 20 | ||||||||||||
20 |
Is the vacuum above the specified value? | 10 in. Hg | Go to Step 21 | Go to Step 26 | ||||||||||||
21 |
Did you find a problem? | -- | Go to Step 27 | Go to Step 22 | ||||||||||||
22 |
Is the test lamp ON? | -- | Go to Step 23 | Go to Step 33 | ||||||||||||
23 |
Is the test lamp ON? | -- | Go to Step 37 | Go to Step 32 | ||||||||||||
24 | Check for leaks or restrictions on the following components:
Did you find a problem? | -- | Go to Step 34 | Go to Diagnostic Aids | ||||||||||||
25 | Check for a restriction or an obstruction in the inlet hose of the AIR pump. Did you find a problem? | -- | Go to Step 34 | Go to Step 38 | ||||||||||||
26 | Repair the leak or restriction in the vacuum source hose to the AIR solenoid. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
27 | Repair the circuit as necessary. Refer to Wiring Repairs or Connector Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
28 | Repair the open in the AIR pump ground circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
Repair the open or short to ground in the battery positive voltage circuit for the AIR pump relay. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 40 | -- | |||||||||||||
30 | Repair the open or short to ground in the ignition positive voltage circuit to the AIR pump relay. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
31 | Repair the short to voltage on the AIR pump relay control circuit. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
32 | Repair the open in the AIR solenoid ground circuit. Refer to Wiring Repairs in Wiring Systems. Is action complete? | -- | Go to Step 40 | -- | ||||||||||||
33 | Repair the open in the AIR solenoid battery positive voltage circuit. Refer to Wiring Repairs in Wiring Systems. Is action complete? | -- | Go to Step 40 | -- | ||||||||||||
34 | Repair the leaks or restrictions as necessary. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement . Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
35 | Replace the AIR pump relay. Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
36 | Replace the AIR shut off valve. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement . Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
37 | Replace the AIR solenoid. Refer to Secondary Air Injection Check Valve and Check Valve Pipe Replacement . Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
38 | Replace the AIR pump. Refer to Secondary Air Injection Pump Replacement . Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
39 |
Important: The replacement VCM must be programmed. Replace the VCM. Refer to VCM Replacement/Programming . Is the action complete? | -- | Go to Step 40 | -- | ||||||||||||
40 |
Does the scan tool indicate the diagnostic Passed? | -- | Go to Step 41 | Go to Step 2 | ||||||||||||
41 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK |
