Housing Assembly HVAC: Testing and Inspection

AIR CONDITIONING UNIT:

INSPECTION





1. INSPECT NO. 1 COOLER THERMISTOR
(a) Measure the resistance.
Standard resistance:





NOTICE:
- Touching the sensor even slightly may change the resistance value. Hold the connector of the sensor.
- When measuring the resistance, the temperature of the sensor and the cooler thermistor must be the same.
HINT: As the temperature increases, the resistance decreases (see the graph).
If the operation is not as specified, replace the cooler thermistor.





2. INSPECT MODE CONTROL SERVO MOTOR
(a) Inspect the servo motor operation.
(1) Connect the positive (+) lead from the battery to terminal 4 (DEF) and negative (-) lead to terminal 5 (FACE), then check that the lever turns to the DEF position smoothly.
Standard:
The motor operates smoothly.
If the operations are not as specified, replace the mode control servo motor.
(2) Connect the positive (+) lead from the battery to terminal 5 (FACE) and negative (-) lead to terminal 4 (DEF), then check that the lever turns to the FACE position smoothly.
Standard:
The motor operates smoothly.
If the operations are not as specified, replace the mode control servo motor.
(b) Check the servo motor resistance.
(1) Using an ohmmeter, measure the resistance and check the results in accordance with the values in the table below.
Standard resistance:






If the result is not as specified, replace the mode control servo motor.






3. REMOVE AIR MIX CONTROL SERVO MOTOR
(a) Inspect the servo motor operation.
(1) Connect the positive (+) lead from the battery to terminal 4 (MH) and negative (-) lead to terminal 5 (MC), then check that the lever turns to the MAX HOT position smoothly.
Standard:
The motor operates smoothly.
If the operations are not as specified, replace the air mix control servo motor.
(2) Connect the positive (+) lead from the battery to terminal 5 (MC) and negative (-) lead to terminal 4 (MH), then check that the lever turns to the MAX COOL position smoothly.
Standard:
The motor operates smoothly.
If the operations are not as specified, replace the air mix control servo motor.
(b) Check the servo motor resistance.
(1) Using an ohmmeter, measure the resistance and check the results in accordance with the values in the table below.
Standard resistance:






If the result is not as specified, replace the air mix control servo motor.