Circuit Description
An 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.
The PCM will activate the AIR pump during closed loop operation. When the AIR system is activated, the PCM will monitor 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.
The PCM checks that the HO2S voltages return to above a rich threshold when the AIR pump is disabled.
If the PCM 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 PCM will set either a DTC P1415 or P1416 to indicate on which bank the AIR system is inoperative.
Conditions for Running the DTC
| • | DTCs P0137, P0138 P0140, P0141, P0143, P0144, P0146, P0147, P0151-P0155, P0157, P0158, P0160, P0161, P0171, P0172, P0174, P0175, P0300, P0500, P1106, P1107, P1111, P1112, P1114, P1115, P1121, P1122, P1133, P1134, P1153, P1154, P1351, P1361 are not set. |
| • | The air flow is less than 22 g/s |
| • | The engine load is less than 33.25 percent |
| • | The air fuel ratio is 13.125:1 |
| • | The engine speed is more than 900 RPM. |
| • | The ECT is between 70°C (158°F) and 110°C (230°F) |
| • | The system voltage is more than 11.7 volts. |
Conditions for Setting the DTC
The HO2S voltage is less than 222 mv for more than 1 second when the AIR pump is turned ON during closed loop operation.
Action Taken When the DTC Sets
The PCM will turn ON the malfunction indicator lamp (MIL) after two consecutive test cycles with the fault active.
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
A low AIR system volume may cause a DTC P1415, 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. |
| • | Restricted or obstructed AIR pump inlet. |
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 a poor connection, rubbed through wire insulation, or a broken wire inside the insulation.
Thoroughly check any circuitry that is suspected of causing the intermittent complaint for the following conditions:
| • | Backed out terminals |
| • | Improper mating |
| • | Broken locks |
| • | Improperly formed or damaged terminals |
| • | Poor terminal to wire connections |
| • | Physical damage to the wiring harness |
| • | Corrosion |
| • | Moisture in the connector |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step determines if the cause of this DTC is still present.
-
This step determines if there is a problem before or after the check valve.
Step | Action | Values | Yes | No | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference:
| ||||||||||||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||||||
Does the Short Term FT (applicable bank) indicate a change of more than the specified value within 30 seconds? | 16% | Go to Step 3 | Go to Step 4 | |||||||||||
3 | The DTC is intermittent. Are any additional DTCs stored? | -- | Go to Diagnostic Aids | |||||||||||
4 | Check the applicable bank AIR System for the following:
Did you find a problem? | -- | Go to Step 8 | Go to Step 5 | ||||||||||
Does air flow from the AIR hose? | -- | Go to Step 6 | Go to Step 7 | |||||||||||
6 | Check for restrictions or leaks in the check valve and the AIR pipe on the applicable bank. Did you find a problem? | -- | Go to Step 8 | Go to Diagnostic Aids | ||||||||||
7 | Check for restrictions or leaks in the applicable bank AIR hose between the check valve and the point where the system branches to each bank. Did you find a problem? | -- | Go to Step 8 | -- | ||||||||||
8 | Repair as necessary. Is the action complete? | -- | Go to Step 9 | -- | ||||||||||
9 |
Does the scan tool indicate that this diagnostic ran and passed? | -- | Go to Step 10 | Go to Step 2 | ||||||||||
10 | Does the scan tool display any additional undiagnosed DTCs? | -- | System OK | |||||||||||
