When to turn off the secondary air injection system?
When the relay is commanded off, the control circuit would have battery voltage present. If the PCM sees a voltage that isn’t what is expected, P0412 will set. Other secondary air injection system trouble codes include P0410, P0411, P0413, P0414, P0415, P0416, P0417, P0418, P0419, P041F, P044F, P0491, and P0492. Symptoms of a P0412 DTC may include:
Where does the air come from for air injection?
A sensitive reed valve assembly called the aspirator valve is placed in the air injection pumping, which draws its air directly from the clean side of the air filter. During engine idle, brief but periodic negative pressure pulses in the exhaust system draw air through the aspirator valve and into the exhaust stream at the catalytic converter.
What is the secondary air injection switching valve?
The Secondary Air Injection System (AIR) Switching Valve is the computer controlled valve that controls the air injection into the exhaust system of the engine (this valve may be integral to the AIR pump).
Why is there a check valve in the air injection system?
A check valve prevents exhaust forcing its way back through the air injection system, which would damage the pump and other components. Carbureted engines’ exhaust raw fuel content tends to spike when the driver suddenly releases the throttle.
When the relay is commanded off, the control circuit would have battery voltage present. If the PCM sees a voltage that isn’t what is expected, P0412 will set. Other secondary air injection system trouble codes include P0410, P0411, P0413, P0414, P0415, P0416, P0417, P0418, P0419, P041F, P044F, P0491, and P0492. Symptoms of a P0412 DTC may include:
The Secondary Air Injection System (AIR) Switching Valve is the computer controlled valve that controls the air injection into the exhaust system of the engine (this valve may be integral to the AIR pump).
What are the symptoms of the air injection system trouble code?
The air injection switching valve voltage is too high indicating an open circuit. The air injection switching valve voltage is too low indicating an short circuit. The ECM sets the code from diagnostic inputs from the air injection system driver. What are the symptoms of the P0412 code?
What kind of problem is an air injection pump?
Defective air injection valve Defective air injection pump Defective one-way check valve Defective pressure sensor Broken, frayed or shorted pressure sensor wiring Broken, frayed or shorted vacuum switching valve wiring Broken, corroded, or melted vacuum switching connector Corroded or damaged pressure sensor connector