FixVault

Circuit/System Verification

  1. If DTCs P0411, P0418, P2432 or P2433 are set, perform those diagnostics first.
  2. Engine running, command the AIR pump relay ON and OFF with a scan tool. Verify that the AIR pump turns ON and OFF with each command.
    • If the AIR pump does not turn ON, the pump may have been damaged by continuous operation. Test or replace the AIR pump. Then, test the AIR pump voltage supply circuit for a short to voltage. If the circuit tests normal, test the AIR pump relay control circuit for a short to ground. If the circuits test normal, test the AIR pump relay. If all circuits and AIR pump relay test normal, replace the engine control module (ECM).
    • If the AIR pump does not turn OFF, test the AIR pump voltage supply circuit for a short to voltage. If the circuits test normal, test the AIR pump relay control circuit for a short to ground. If all circuit test normal, test the AIR pump relay. If all circuits and the AIR pump relay test normal, replace the ECM.