Secondary Air Injection System Diagnosis

Diagnostic Chart (Part 1 Of 4):

Diagnostic Chart (Part 2 Of 4):

Diagnostic Chart (Part 3 Of 4):

Diagnostic Chart (Part 4 Of 4):

Schematic:

CIRCUIT DESCRIPTION
A fused ignition voltage is supplied to the AIR pump relay. The VCM controls the AIR pump by grounding the AIR pump relay control circuit. This energizes the relay and supplies voltage to the AIR Pump and the AIR solenoid. When the fuel system goes into closed loop, the VCM opens the ground to the AIR control circuit.

DIAGNOSTIC AIDS
An AIR pump that is stuck on could cause a fuel trim lean code.

An AIR solenoid or AIR shut off valve that is stuck open could allow the exhaust system to draw air in unintentionally through the AIR system.

An AIR supply hose that is melted before the check valve could indicate exhaust gas back-flow past the check valve.

A low AIR system volume may cause a DTC P1415, P1416 or an intermittent complaint. Also check for the following conditions:
^ Pinched, kinked, or restricted AIR pipes, hoses, or fittings
^ Leaks, holes, loose fittings or hoses
^ A restricted or obstructed AIR pump inlet

An intermittent may be caused by any of the following conditions:
^ A poor connection
^ Rubbed through wire insulation
^ A broken wire inside the insulation

Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in Diagrams.

If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Diagrams.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. This step will determine if the AIR System is functioning correctly.
5. This step will ensure that the VCM is capable of turning the AIR pump OFF.
16. This step will determine if the VCM is capable of controlling the AIR pump relay.
19. This step is to check for a short to voltage on the control circuit.
20. The engine must be running for this test to ensure a vacuum supply to the system.
21. This step is to check for an AIR solenoid stuck open.
22. This step is to ensure the AIR shut off valve closes when the vacuum supply is removed.
23. This step will determine if the AIR pump is capable of producing airflow.
36. An open fuse for the battery feed circuit could be caused by a short to ground in the components operated by the relay. Also check the wiring in the circuits on the switched side of the relay. Refer to Diagnostic Aids.