Possible causes
– AIR relay fault – stuck closed
– Secondary AIR pump fault – circuit open in motor
– Open ground to secondary AIR pump
– Open AIR monitor circuit between the secondary AIR pump and the PCM
– Short to voltage in the AIR relay to secondary AIR pump voltage circuit
– Secondary AIR pump fault – circuit open in motor
– Open ground to secondary AIR pump
– Open AIR monitor circuit between the secondary AIR pump and the PCM
– Short to voltage in the AIR relay to secondary AIR pump voltage circuit
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)