Ignition "OFF"
Disconnect Driver air mix actuator and connect A/C control unit main harness connector.
Connect (+) terminal of battery to WARM(+) of Driver air mix actuator and (-) terminal to COOL(-). (Component side)
Verify that the Air mix actuator(Temperature actuator) operates to the WARM position.
Verify that the Air mix actuator(Temperature actuator) operates to the COOL position reversing the connection polarity.(COOL(+) and WARM(-) ) .(Component side)
Specification : Refer the specifications in Fig.1)
Actuator harness | WARM(+) | COOL(-) | Door position |
Battery terminal | 12 V | ground | Max.warm |
ground | 12 V | Max.cool |
Fig.1) ※ Function of the actuator motor according to terminal connection type. (observe safety regulations)
Is "Door position" display within specifications?
 | ▶ Go to "Check potentiometer" procedure. |
 | ▶ Substitute with a known-good Driver air mix actuator and check for proper operation. If the problem is corrected, replace Driver air mix actuator and then go to "Verification of Vehicle Repair" procedure. |
Ignition "OFF"
Connect Driver air mix actuator and A/C control unit main harness connector.
Ignition "ON"
Measure voltage between Signal(F/B) terminal of Driver air mix actuator harness connector and Sensor ground(-) terminal of A/C-ECU harness connector .(Component side)
Specification : Refer the specifications in Fig.2)
Door position | Voltage |
Max. cool | 0.4 V±0.3V |
Max. warm | 4.6 V±0.3V |
Fig.2) ※ Voltage value of Air Mix potentiometer as a function of temp door position.
Is "voltage" display within specifications?
| ▶ Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure. |
| ▶ Substitute with a known-good Driver air mix actuator and check for proper operation. If the problem is corrected, replace Driver air mix actuator and then go to "Verification of Vehicle Repair" procedure. |
