General Information

Certain vehicles may be equipped with a secondary air injection (AIR) system. The AIR system lowers the tail pipe emissions on start-up. The PCM grounds the AIR pump relay control circuit, which energizes the AIR pump. The PCM also grounds the AIR solenoid valve control circuit, which energizes the AIR solenoid valve. The AIR solenoid valve opens allowing a manifold vacuum to open the AIR control valves. The PCM enables both control circuits when AIR system operation is desired. When the AIR system is active, the AIR pump forces fresh air into the exhaust stream which accelerates the catalyst operation. The AIR control valves replace the conventional check valves. When the AIR system is inactive, the AIR control valves prevent any air flow in either direction.

A DTC P0412 applies to the AIR solenoid control circuit. A DTC P0418 applies to the AIR pump relay control circuit. A DTC P0410 sets if an air flow problem is detected.