| Circuit Diagram |

Signal Waveform
Inspection1.Turn the ignition switch OFF and disconnect the battery negative (-) cable.2.Disconnect the fuel pressure regulator valve connector.3.Measure resistance between the fuel pressure regulator valve terminals 1 and 2.
Inspection1.Turn the ignition switch OFF.2.Disconnect the mode control actuator connector.3.Verify that the mode control actuator operates to the defrost mode when connecting 12V to terminal 3 and grounding terminal 4.Verify that the mode control actuator operates to the vent mode when connected in reverse.
Inspection1.Turn the ignition switch OFF.2.Disconnect the intake actuator connector.3.Verify that the intake actuator operates to the fresh position when connecting 12V to terminal 3 and grounding terminal 4.Verify that the intake actuator operates to the recirculation position when connected in reverse.