Initial Inspection
ON-VEHICLE INSPECTION1. Air conditioner function check
a. Install the air conditioner tool set.
b. Set the vehicle to the conditions shown [*1].
HINT:
- *2 Since the correct judgment can be done only when the inlet air temperature stays between 25°C and 35°C, postpone the test if the temperature is lower than 25°C.
- *3 When the condenser pressure (high pressure side gauge) is higher than 1.5 Mpa (15.5 kgf/sq.cm), water the condenser to decrease pressure. When the condenser pressure is too low, cover the front side of the condenser to increase pressure.
c. Place a dry and wet bulb thermometer at the air inlet opening and insert the bulb of a dry bulb thermometer at the center of the air outlet opening.
d. Operate the air conditioner by following [*1] and stabilize the air outlet opening temperature (approx. 5 to 6 minutes).
e. Measure the dry and wet bulb temperature at the air inlet opening and the dry bulb temperature at the air outlet opening.
f. Using the psychrometric chart, determine the relative humidity value, based on the measured values of the wet and dry bulb thermometers in the inlet.
1. For example, when the dry bulb temperature is 25 degrees Celsius and the wet bulb temperature is 19.5 degrees Celsius, the relative humidity value is 60%, which is shown in the psychrometric chart as the point where the 2 dotted lines intersect.
g. Using the standard performance chart below, find the point where the difference between the temperatures measured in the inlet and outlet, and the relative humidity intersect.
Standard:The intersecting point is within the diagonal range shown in the chart.
*1. For example, when the difference between temperatures measured in the inlet and outlet is 17 degrees Celsius and the relative humidity is 60%, the intersecting point is within the diagonal range. Therefore this air conditioner is normal.
2. INSPECT PRESSURE SWITCH NO.1
a. Magnetic clutch control:
Inspect pressure switch operation.
1. Set the manifold gauge.
2. Connect the positive (+) lead from the ohmmeter to terminal 4 and the negative (-) lead to terminal 1.
3. Check continuity between the terminals when refrigerant pressure is changed, as shown in the illustration.
If operation is not as specified, replace the liquid tube sub assy A.
b. Cooling fan control: Inspect pressure switch operation.
1. Connect the positive (+) lead from the ohmmeter to terminal 2 and the negative (-) lead to terminal 3.
2. Check continuity between the terminals when refrigerant pressure is changed, as shown in the illustration.
If operation is not specified, replace the liquid tube sub assy A.
3. INSPECT AIR CONDITIONER AMPLIFIER ASSY
a. Disconnect the connector from A/C amplifier and inspect the wire harness side, as shown in the chart.
If the circuit is as not specified, replace the A/C amplifier with a new one. If the circuit is as specified, inspect the circuits connected to other parts.
b. Connect the connector to A/C amplifier and inspect wire harness side connector from the back side, as shown in the illustration.
If the circuit is not as specified, replace the A/C amplifier with a new one. If the circuit is as specified, inspect the circuits connected to other parts.
Reference
Reference
4. INSPECT ECM
a. Measure the resistance and voltage according to the value(s) in the table
5. INSPECT W/PULLEY COMPRESSOR ASSY
a. Check the operation.
1. Start the engine.
2. Inspect the compressor pulley.
Standard: The compressor shaft rotates along with the pulley
b. Inspect w/pulley compressor assy.
1. Disconnect the connector.
2. Measure the resistance according to the value(s) in the table.
c.
1. When the refrigerant amount and congestion of A/C cycle cannot be checked by the condition of the sight glass and manifold gauge, connect the positive battery cable to terminal 1 of the connector and the negative battery cable to the terminal 2 of the connector, and then check if cold air comes out while setting the blower switch to the "LO" position.