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. |
