Circuit Description
WARNING: This page is about a different variant/trim than selected.
To accelerate the activation of the Three-Way Catalytic Converter (TWC) when warming up the engine, the air injection system pumps secondary air to the exhaust manifold using pressure. The secondary air is supplied by the air pump and is pumped to the exhaust manifold through the air switching valve. The opening and closing movements of the air switching valve are regulated by the Vacuum Switching Valve (VSV). The air pump and air switching valve are monitored by the ECM and are used to detect malfunctions in this system. The ECM monitors the secondary air injection system and detects malfunctions using the pressure sensor located on the air switching valve.