Flowchart No. 10: Airflow Temperature Does Not Change

System Operation
The air mix actuator adjusts the opening of the mix door by using a link and rod mechanism.

A potentiometer attached to the link outputs a signal to the heater control unit. This signal changes as the position of the door changes. The door position is adjusted based on the temperature control lever selling on the heater control unit.


Step 1
1. Disconnect the air mix actuator connector.








2. Connect battery positive voltage to terminals G and H of the air mix actuator and check the actuator operation.
3. If correct, go to Step 2.
4. If not as specified, replace the air mix actuator.


Step 2
1. Verify that the air mix actuator connector is disconnected.





2. Connect battery positive voltage to terminals G and H, and measure the resistance of the air mix actuator.








3. Compare the measurement resistance to the characteristics shown in the figure.


Step 3
1. Disconnect the air mix actuator connector and heater control unit connector.








2. Check for continuity at the following terminal wires between the connectors.