Possible Causes
Faulty Secondary Air System Relay
Secondary Air System Relay harness is open or shorted
Secondary Air System Relay circuit poor electrical connection
Faulty Secondary Air System Pump
الأسباب المحتملة
Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
الأعراض المحتملة
Description
An Air Pump is used on the vehicle to lower tail pipe emissions on start-up. The Powertrain Control Module (PCM) grounds the Air Pump Relay Control Circuit which energizes the Air Pump. The PCM also grounds the Air Combination Valve Vacuum Control Solenoid Circuit, which energizes the Air Vacuum Control Solenoid. Vacuum is then applied to both Air Combination Valve Diaphragms which opens the shut-off valves. The PCM enables both circuits simultaneously when Air System operation is desired. When the Air System is active, then Air pump forces fresh air into the exhaust stream in order to accelerate catalyst operation. The AIR combination valves replace the conventional check valves. When the AIR system is inactive the shut-off valves prevent air flow in either direction.
