| Circuit Diagram |

Signal Waveform
Inspection 1. Turn the ignition switch OFF. 2. Disconnect the HO2S connector. 3. Measure resistance between the HO2S terminals 1 and 2. 4.
C
Inspection 1. 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.