AIR CONDITIONING SYSTEM Cooling is Poor

DESCRIPTION

If the cooling air is poor (cooling air is discharged), the following causes are possible.

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. CHECK ECO DRIVE MODE OPERATION

   
   

   1. Confirm setup of the ECO drive mode and turn it off if it becomes ON.

      Tech Tips

      
      

      • When ECO drive mode is on, the air conditioning amplifier assembly ensures a minimum level of air conditioning control based on certain conditions, thereby contributing to improved fuel efficiency. Accordingly, explain to customers that the air volume will be weaker in these situations.

        Control
        Airflow Control	Automatically switches the air inlet port to the internal air circulation mode when the outside air temperature is equal to or higher than a predetermined temperature and reduces the power consumption.
        Air Inlet Control	Sets the blower level in AUTO mode lower than normal, and suppresses the power consumption.

      • If satellite switch set is malfunctioning, perform diagnosis on the ECO switch circuit.

        Click here

      Result
      Proceed to NEXT

   
   

   NEXT

2. CHECK REFRIGERANT PRESSURE

   
   

   1. Connect the Techstream to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the Techstream on.

   4. Enter the following menus: Body Electrical / Air Conditioner / Data List.

   5. Read the Data List according to the display on the Techstream.

      
      Body Electrical > Air Conditioner > Data List

      Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
      Regulator Pressure Sensor	Air conditioner pressure sensor	Min.: -456.6 kPaG Max.: 3294.3 kPaG	Actual refrigerant pressure displayed	Refrigerant line (gas leak etc.) Air conditioner pressure sensor system malfunction

      
      Body Electrical > Air Conditioner > Data List

      Tester Display
      Regulator Pressure Sensor

   6. Install a manifold gauge set.

      
      

      • for HFC-134a (R134a): Click here

      • for HFO-1234yf (R1234yf): Click here

   7. Read the manifold gauge pressure when the following conditions are met.

      
      

      1. Prepare the vehicle according to the table below.

         Measurement Condition:

         Item	Condition
         Vehicle doors	Fully open
         Temperature setting	MAX COLD
         Blower speed	HI
         A/C switch	On
         Recirculation/fresh switch	RECIRCULATION
         Interior temperature	25 to 35°C (77 to 95°F)

      Standard Pressure
      Low pressure side
      150 to 250 kPa (1.5 to 2.5 kgf/cm2, 22 to 36 psi)
      High pressure side
      1370 to 1570 kPa (14 to 16 kgf/cm2, 199 to 228 psi)

   8. Compare the values displayed in the Data List and on the manifold gauge.

      OK
      The values displayed in the Data List and on the manifold gauge match.

      Result
      Proceed to OK NG

   
   

   NG

   CHARGE SYSTEM WITH REFRIGERANT for HFC-134a (R134a): Click here for HFO-1234yf (R1234yf): Click here

   OK

3. PERFORM ACTIVE TEST USING GTS (AIR MIX SERVO TARG PULSE (D), AIR MIX SERVO TARG PULSE (P))

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the GTS on.

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

   5. Check the operation by referring to the table below.

      
      Body Electrical > Air Conditioner > Active Test

      Tester Display	Measurement Item	Control Range	Restrict Condition
      Air Mix Servo Targ Pulse(D)	for LHD: No. 2 air conditioning radiator damper servo sub-assembly (driver side upper air mix) operation for RHD: No. 4 air conditioning radiator damper servo sub-assembly (driver side upper air mix) operation	Min.: 128 Max.: 383	for LHD: Operates between 254 to 326 pulses for RHD: Operates between 186 to 258 pulses
      Air Mix Servo Targ Pulse(P)	for LHD: No. 4 air conditioning radiator damper servo sub-assembly (front passenger side upper air mix) operation for RHD: No. 6 air conditioning radiator damper servo sub-assembly (front passenger side upper air mix) operation	Min.: 128 Max.: 383	for LHD: Operates between 186 to 258 pulses for RHD: Operates between 254 to 326 pulses

      
      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)

      OK
      Damper servo motor is operated.

      Result
      Proceed to OK NG

   
   

   NG

   GO TO DTC OF APPLICABLE SERVO MOTOR OPERATING ABNORMALLY Click here

   OK

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

   
   

   1. Disconnect the G16 automatic light control sensor connector.

   2. Disconnect the G12 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 Q6-1 (CLTB) - G12-23 (CLTB) Always Below 1 Ω Q6-2 (CLTE) - G12-25 (CLTE) Always Below 1 Ω Q6-4 (CLTS) - G12-24 (CLTS) Always Below 1 Ω Q6-1 (CLTB) or G12-23 (CLTB) - Other terminals and body ground Always 10 kΩ or higher Q6-2 (CLTE) or G12-25 (CLTE) - Other terminals and body ground Always 10 kΩ or higher Q6-4 (CLTS) or G12-24 (CLTS) - Other terminals and body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. 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

   GO TO ON-VEHICLE INSPECTION Click here

   NG

   REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here