DTC 18


DTC 18	Air mix actuator (potentiometer) (present)
POSSIBLE CAUSE	• Air mix actuator malfunction • Climate control unit malfunction • Open circuit between air mix actuator and climate control unit • Short circuit between air mix actuator (terminal C) and climate control unit (terminal 1U: 24-pin)


STEP	INSPECTION		ACTION
1	• Inspect air mix actuator. • Is it okay?	Yes	Go to the next step.
1	• Inspect air mix actuator. • Is it okay?	No	Replace air mix actuator.
2	• Disconnect airflow mode actuator connector. • Is resistance between terminals 1U and 1I of climate control unit connector (24-pin) more than 387 ohms?	Yes	Go to the next step.
2		No	Repair wiring harness. (Short circuit)
3	• Disconnect climate control unit connector (24-pin). • Is resistance between terminals 1B and 1I of climate control unit connector (24-pin) less than 4.8 kilohms?	Yes	Go to the next step.
3		No	Repair wiring harness. (Open circuit)
4	• Is resistance between terminals 1B and 1U of climate control unit connector (24-pin) less than 4.2 kilohms?	Yes	Replace climate control unit.
4		No	Repair wiring harness. (Open circuit)