3.
Measure voltage value between terminal "B1" of A/C control unit and chassis ground.
a.
Specification : 5V
Engine "ON".
Disconnect passenger air mix actuator.
Measure voltage value between terminal "B1" of A/C control unit and chassis ground.
Specification : 5V
Is the measured voltage within specifications?
YES
Go to "Check passenger air mix actuator" procedure.
NO
Substitute with a known-good A/C Control Unit and check for proper operation.
If the problem is corrected, replace A/C Control Unit and then go to "Verification of Vehicle Repair" procedure.
Check actuator motor
Ignition "OFF".
Disconnect passenger air mix actuator.
Connect (+) terminal of battery to terminal 3 of passenger air mix actuator and (-) terminal to terminal 4.
Verify that the temperature actuator operates to the hot position.
Verify that the temperature actuator operates to the cool position with reverse connecting.( (+) to 4 and (-) to 3)
Dose the actuator work properly?
YES
Go to "Check potentiometer" procedure.
NO
Substitute with a known-good actuator and check for proper operation. If the problem is corrected, replace actuator and then go to "Verification of Vehicle Repair" procedure.
Check actuator potentiometer
Ignition "ON".
Connect passenger air mix actuator.
Measure voltage between terminal "5" and "6" of passenger air mix actuator while operating the temp switch.
Specification : Refer the specifications in fig3)
Door position | Voltage | Error Detecting Condition |
Max. cool | 0.3±0.15V | Undervoltage : 0.08V or less |
Max.warm | 4.7±0.15V | Overvoltage : 4.9V or more |
Fig3) Specifications : Voltage value of Air Mix potentiometer as a function of temp door position.
Is the measured voltage within specifications in fig3)?
YES
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.
NO
Substitute with a known-good actuator and check for proper operation. If the problem is corrected, replace actuator and then go to "Verification of Vehicle Repair" procedure.
