AIR CONDITIONING SYSTEM, Diagnostic DTC:B14B2

DTC Code DTC Name
B14B2 Lost Communication with Front Panel LIN

DESCRIPTION

The air conditioning control assembly communicates with the air conditioning amplifier assembly via LIN communication.

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

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B14B2 Lost Communication with Front Panel LIN Lost communication with air conditioning control assembly

  • Harness or connector between air conditioning control assembly and engine stop and start ECU*2

  • Harness or connector between air conditioning control assembly and IG power source*3

  • Harness or connector between air conditioning control assembly and body ground

  • LIN communication system

  • Air conditioning control assembly

  • Air conditioning amplifier assembly

Memorized

(10 sec. or more)*1

WIRING DIAGRAM

B00777PE04

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CONFIRM MODEL


    1. Choose the model to be inspected.

      Result
      Result Proceed to
      w/o Stop and Start System A
      w/ Stop and Start System B

    B

    CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - ENGINE STOP AND START ECU) Click here

    A

  2. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - IG POWER SOURCE)


    1. Disconnect the O64 air conditioning control assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      O64-8 (IG+) - Body ground Engine switch off Below 1 V
      O64-8 (IG+) - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - BODY GROUND)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      O64-14 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 7 Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - ENGINE STOP AND START ECU)


    1. Disconnect the O64 air conditioning control assembly connector.

    2. Disconnect the O143 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
      O64-8 (IG+) - O143-3 (IG41) Always Below 1 Ω
      O64-8 (IG+) or O143-3 (IG41) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - BODY GROUND)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      O64-14 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING CONTROL ASSEMBLY - IG POWER SOURCE)


    1. Reconnect the O143 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
      O64-8 (IG+) - O64-14 (GND) Engine switch off Below 1 V
      O64-8 (IG+) - O64-14 (GND) Engine switch on (IG) 10.5 to 16 V
      Result
      Proceed to
      OK
      NG

    NG

    GO TO STOP AND START SYSTEM Click here

    OK

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


    1. Disconnect the O9 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
      O64-6 (LIN1) - O9-21 (RLIN) Always Below 1 Ω
      O64-6 (LIN1) or O9-21 (RLIN) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. REPLACE AIR CONDITIONING CONTROL ASSEMBLY


    1. Replace the air conditioning control assembly.

      Click here

      Tech Tips

      Since the air conditioning control assembly cannot be inspected while it is removed from the vehicle, replace the air conditioning control assembly with a new or known good one and check that the condition returns to normal.

      OK
      Air conditioning control assembly operation returns to normal.
      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 (AIR CONDITIONING CONTROL ASSEMBLY WAS DEFECTIVE)

    B

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

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here