Secondary Air Injection System Monitor (Belt Driven Air Pump System)
The Secondary Air Injection (AIR) system monitor is an on-board strategy designed to monitor the proper function of the secondary air system. The AIR monitor for the belt driven air pump system consists of two Output State Monitor configurations in the Powertrain Control Module (PCM); one circuit monitors the electrical circuit of the Secondary Air Injection Bypass (AIRS) solenoid, the second circuit monitors the electrical circuit of the Secondary Air Injection Diverter (AIRD) solenoid. A functional check is also performed that tests the ability of the AIR system to inject air into the exhaust. The functional check relies upon HO2S sensor feedback to determine the presence of air flow. The monitor is enabled during AIR system operation and only after certain base engine conditions are first satisfied. Input is required from the ECT, IAT, and CKP sensor, and the HO2S monitor must also have passed without a fault detection to enable the AIR monitor. The AIR monitor is also activated during on demand self-test. The following examples are probable conditions:
- The AIRB solenoid circuit is monitored for open and shorted conditions by the AIRB output state monitor. See Fig 1. The DTCs associated with this test are DTCs P0413 and P0414.
- The AIRD solenoid circuit is monitored for open and shorted conditions by the AIRD Output State Monitor. The DTCs associated with this test are DTCs P0416 and P0417.
- An upstream and downstream functional air flow test is performed during idle, once per engine start-up, and only after all HO2S monitor tests have been successfully performed. The flow test relies upon the upstream and downstream HO2S to detect the presence of additional air in the exhaust when introduced by the Secondary Air Injection system. The DTCs associated with this test are DTCs P0411 and P1411.
- The Malfunction Indicator Light (MIL) is illuminated after one of the above tests fail on 2 consecutive drive cycles.