P1416

CIRCUIT DESCRIPTION
The Secondary Air Injection (AIR) pump used on this vehicle lowers the tail pipe emissions during start-up.

The AIR system consists of the following components:
^ The AIR pumps
^ The shut-off valves
^ The vacuum control solenoid valve
^ The system hoses and pipes
^ The AIR relays, the fuses, and the related wiring.

The Powertrain Control Module (PCM) uses the AIR relay in order to control the AIR pump. The PCM also controls the AIR vacuum control solenoid valve that supplies the vacuum to the AIR shut-off valves. With the AIR system inactive, the AIR shut-off valves prevent air flow in either direction. With the AIR system active, the PCM applies ground to the AIR relay, and the vacuum control solenoid valve. Fresh air flows from the pump, through the system hoses, past the shut-off valves, and into the exhaust stream. The air helps the catalyst to quickly get to a working temperature, lowering the tail pipe emissions during a start-up. The PCM tests the following AIR system components:
^ The overall AIR system, including both banks- Any problems detected here will result in Diagnostic Trouble Code (DTC) P0410.
^ The AIR system bank 1 (DTC P1415)
^ The AIR system bank 2 (DTC P1416)
^ The AIR relay (DTC P0418)
^ The AIR vacuum control solenoid valve (DTC P412)

The PCM runs a passive test and an active test in order to diagnose the AIR system. Both tests involve a response from the fuel control HO2S (HO2S bank 1 sensor 1 and HO2S bank 2 sensor 2). The passive test consists of 2 parts. If both passive tests pass, the PCM takes no further action. If either part of the passive test fails or is inconclusive, the PCM initiates the active tests. If the PCM determines that the HO2S bank 2 sensor 1 did not respond as expected during the tests, DTC P1416 will set. For further information concerning the AIR system and the system tests, refer to Secondary Air Injection (AIR) System Description.

CONDITIONS FOR RUNNING THE DTC

Passive Tests:
^ The engine is running.
^ The engine speed is more than 600 RPM.
^ The throttle is steady.
^ The engine load is less than 80 percent.
^ The system voltage is more than 10.5 volts.
^ The Mass Air Flow (MAF) is less than 35 g/s.
^ The air/fuel ratio is more than 12.5:1.
^ The Engine Coolant Temperature (ECT) is between 0-108°C (32-226°F).
^ The IAT is between 0-60°C (32-140°F).
^ The power enrichment, or deceleration fuel cut-off is not active.

Active Tests:
^ The engine is running.
^ The engine speed is more than 600 RPM.
^ The throttle is steady.
^ The engine load is less than 80 percent.
^ The system voltage is more than 10.5 volts.
^ The MAF is less than 35 g/s.
^ The fuel system is in closed-loop operation.
^ The EVAP purge is active.
^ The ECT is above 68°C (154°F).

CONDITIONS FOR SETTING THE DTC

Passive Tests:
^ During the operation of the AIR pump, the HO2S bank 2 sensor 1 voltage remains above 470 mV for 20 seconds, and above 450 mV for 7 seconds during a hot start.

OR

With the AIR pump commanded OFF, the HO2S bank 2 sensor 1 voltage remains below 700 mV for 25 seconds.
^ The PCM initiates the active test due to a failed or an indeterminate passive test.

Active Test:
^ A failed or an indeterminate passive test has occurred.
^ The HO2S bank 2 sensor 1 voltage remains above 35 mV.
^ The PCM detects a failed passive test and 2 failed active tests.

OR

The PCM records an indeterminate passive test and 3 active tests.

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.
^ Use a scan tool in order to clear the MIL and the DTC.

DIAGNOSTIC AIDS
If the condition is intermittent, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-9:

The number below refers to the step number on the diagnostic table:
3. A check valve that flows in both directions causes heat damage to the AIR system components.