AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System) Cooling is Poor

DESCRIPTION

If the cooling effect of the air conditioning system is weak, the following factors may be the cause.

• *1: w/ ECO Switch

• *2: except 2GR-FKS

• *3: for 2GR-FKS

WIRING DIAGRAM

*a	Air Conditioning Amplifier Assembly
*b	Automatic Light Control Sensor
*c	Main Body ECU (Multiplex Network Body ECU)
*d	CAN Communication Line

PROCEDURE

1. CONFIRM MODEL

   Result
   Result Proceed to w/ ECO Switch A w/o ECO Switch B

   
   

   B

   GO TO STEP 3 Click here

   A

2. CHECK ECO MODE CONTROL OPERATION

   
   

   1. Check that ECO mode control is disabled (ECO mode indicator is not illuminated).

   2. Operate the ECO switch assembly (electric parking brake switch assembly) and check that the ECO mode indicator illuminates and the blower speed is reduced.

      Tech Tips

      
      

      • When ECO mode control is operating, the air conditioning amplifier assembly controls the air conditioning system to enhance fuel efficiency. Therefore, explain to the customer that, when ECO mode control is operating, the blower speed will be reduced.

        Control	Outline
        Blower Control	When the air conditioning system is in AUTO mode, the blower speed will be reduced to a certain speed. Additionally, if warm-up control is operating, the blower speed will be further reduced.
        Air Inlet Control	If the ambient temperature is a certain value or more, the air inlet mode will be changed to recirculation mode.

      • In some situations, ECO mode control may not operate even though it is enabled.

   3. Operate the ECO switch assembly (electric parking brake switch assembly) and check that the ECO mode indicator turns off and the blower speed returns to normal.

      OK
      When the ECO switch assembly (electric parking brake switch assembly) is operated, ECO mode control is enabled/disabled and the blower speed is controlled.

      Result
      Proceed to OK NG

   
   

   NG

   GO TO ECO Switch Circuit Click here

   OK

3. PERFORM REFRIGERANT SHORTAGE CHECK

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Air Conditioner / Utility / Refrigerant Gas Volume Check.

      
      Body Electrical > Air Conditioner > Utility

      Tester Display
      Refrigerant Gas Volume Check

   5. Check that the following conditions are met and perform the refrigerant shortage check according to the display on the GTS.

      Measurement Condition:

      Item	Condition
      A/C switch	On
      Ambient temperature*	0 to 49°C (32 to 120°F)
      Blower speed	HI

      *: If the ambient temperature is not within the range shown, do not perform this check.

      Result
      Result Amount of Refrigerant Refrigerant correct Correct Refrigerant shortage Insufficient

      OK
      "Refrigerant correct" is displayed on the GTS.

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR REFRIGERANT LEAK Click here

   OK

4. PERFORM ACTIVE TEST USING GTS

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Air Conditioner / Active Test.

   5. Perform the Active Test according to the display on the GTS.

      
      Body Electrical > Air Conditioner > Active Test

      Tester Display	Measurement Item	Control Range	Diagnostic Note
      Air Mix Servo Targ Pulse(D)	No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) pulse	Min.: 128 Max.: 383	for LHD Operates between 165 to 257 pulses for RHD Operates between 255 to 347 pulses
      Air Mix Servo Targ Pulse(P)	No. 1 air conditioning radiator damper servo sub-assembly (front passenger side air mix) pulse	Min.: 128 Max.: 383	for LHD: Operates between 255 to 347 pulses for RHD: Operates between 165 to 257 pulses
      Rear Air Mix Servo Targ Pulse	No. 3 air conditioning radiator damper servo sub-assembly pulse	Min.: 128 Max.: 383	Operates between 165 to 257 pulses *

      
      

      • *: for 3 Zone Type

      
      Body Electrical > Air Conditioner > Active Test

      Tester Display
      Air Mix Servo Targ Pulse(D)

      
      Body Electrical > Air Conditioner > Active Test

      Tester Display
      Air Mix Servo Targ Pulse(P)

      
      Body Electrical > Air Conditioner > Active Test

      Tester Display
      Rear Air Mix Servo Targ Pulse

      OK
      Each damper servo motor operates.

      Result
      Proceed to OK NG

   
   

   NG

   GO TO DTC TROUBLESHOOTING PROCEDURE FOR MALFUNCTIONING DAMPER SERVO MOTOR Click here

   OK

5. INSPECT HARNESS AND CONNECTOR (AUTOMATIC LIGHT CONTROL SENSOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

   
   

   1. Disconnect the M1 automatic light control sensor connector.

   2. Disconnect the K52 main body ECU (multiplex network body ECU) connector.

   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition M1-1 (CLTB) - K52-23 (CLTB) Always Below 1 Ω M1-2 (CLTE) - K52-25 (CLTE) Always Below 1 Ω M1-4 (CLTS) - K52-24 (CLTS) Always Below 1 Ω M1-1 (CLTB) or K52-23 (CLTB) - Other terminals and body ground Always 10 kΩ or higher M1-2 (CLTE) or K52-25 (CLTE) - Other terminals and body ground Always 10 kΩ or higher M1-4 (CLTS) or K52-24 (CLTS) - Other terminals and body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

6. INSPECT AUTOMATIC LIGHT CONTROL SENSOR

   
   

   1. Remove the automatic light control sensor.

      Click here

   2. Inspect the automatic light control sensor.

      Click here

      Result
      Proceed to OK NG

   
   

   OK

   INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET Click here

   NG

   REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here