AIR CONDITIONING SYSTEM, Diagnostic DTC:B14B3

DTC Code DTC Name
B14B3 Lost Communication with Rear Panel LIN

DESCRIPTION

The cooler control switch assembly communicates with the air conditioning amplifier assembly through the LIN communication system.

If the LIN communication system malfunctions, the air conditioning amplifier assembly does not operate even if the cooler control switch assembly is operated.

DTC No. DTC Detection Condition Trouble Area
B14B3 Lost communication with the cooler control switch assembly.

  • Harness or connector between cooler control switch assembly and power source circuit

  • Harness or connector between cooler control switch assembly and body ground

  • Harness or connector between cooler control switch assembly and engine stop and start ECU*

  • LIN communication system

  • Cooler control switch assembly

  • Air conditioning amplifier assembly

  • Engine stop and start ECU*

WIRING DIAGRAM

A01W49WE01

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CONFIRM MODEL


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      except 6AR-FSE A
      for 6AR-FSE B

    B

    CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - POWER SOURCE CIRCUIT) Click here

    A

  2. CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - POWER SOURCE CIRCUIT)


    1. Disconnect the h2 cooler control switch assembly connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      h2-1 (+B) - Body ground Always 11 to 14 V
      h2-7 (IG+) - Body ground Engine switch off Below 1 V
      h2-7 (IG+) - Body ground Engine switch on (IG) 11 to 14 V
      h2-6 (ACC) - Body ground Engine switch off Below 1 V
      h2-6 (ACC) - Body ground Engine switch on (ACC) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - BODY GROUND)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      h2-16 (GND) - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      NG A
      OK B

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    B

    CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - COOLER CONTROL SWITCH ASSEMBLY) Click here

  4. CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - POWER SOURCE CIRCUIT)


    1. Disconnect the h2 cooler control switch assembly connector.

    2. Disconnect the H191 engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      h2-1 (+B) - H191-2 (B41) Always Below 1 Ω
      h2-7 (IG+) - H191-3 (IG41) Always Below 1 Ω

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      h2-6 (ACC) - Body ground Engine switch off Below 1 V
      h2-6 (ACC) - Body ground Engine switch on (ACC) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - BODY GROUND)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      h2-16 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (COOLER CONTROL SWITCH ASSEMBLY - ENGINE STOP AND START ECU)


    1. Reconnect the H191 engine stop and start ECU connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      h2-1 (+B) - h2-16 (GND) Always 9.5 to 14 V
      h2-7 (IG+) - h2-16 (GND) Engine switch off Below 1 V
      h2-7 (IG+) - h2-16 (GND) Engine switch on (IG) 11 to 14 V

    NG

    GO TO STOP AND START SYSTEM Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - COOLER CONTROL SWITCH ASSEMBLY)


    1. Disconnect the H54 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      h2-10 (RLIN) - H54-37 (LIN1) Always Below 1 Ω
      h2-10 (RLIN) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. REPLACE COOLER CONTROL SWITCH ASSEMBLY


    1. Replace the cooler control switch assembly Click here.

      Tech Tips

      Since the cooler control switch assembly cannot be inspected while it is removed from the vehicle, replace the cooler control switch assembly with a new or known good one and same problem occurs again.

      OK
      Same problem does not occurs.
      Result
      Result Proceed to
      OK A
      NG (When troubleshooting according to Problem Symptoms Table) B
      NG (When troubleshooting according to the DTC) C

    A

    END (COOLER CONTROL SWITCH ASSEMBLY WAS DEFECTIVE)

    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here