Results of Incorrect Operation

If no air flow enters the exhaust stream, the start-up emission levels will rise. The control module can detect a system flow problem using the pre-catalyst HO2S and the short term fuel trim. If a system flow problem exists, the HO2S voltage will not indicate an expected lean condition. The short term fuel trim will not increase, and a DTC will set.

If incorrect voltage is present on the vacuum control solenoid or on the pump relay control circuits, the device will not operate. The control module will detect this condition, and a DTC will set.

If a secondary air injection fault is detected. the following DTCs can set:
^ P0410-A system flow problem has been detected.
^ P0412-A vacuum control solenoid control circuit problem has been detected.
^ P0418-A pump relay control circuit problem has been detected.
^ P1415-A Bank 1 flow problem has been detected.
^ P1416-A Bank 2 flow problem has been detected.