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 through the LIN communication system.

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

Note

B14B2

Lost Communication with Front Panel LIN

Lost communication with the air conditioning control assembly.

  • Harness or connector

  • LIN communication system

  • Air conditioning control assembly

  • Air conditioning amplifier assembly

Memorized (10 seconds or more)

-
Tip:

The air conditioning amplifier assembly stores the DTC of the respective malfunction if it has occurred for the period of time indicated in the parentheses.

WIRING DIAGRAM

E313779E11

CAUTION / NOTICE / HINT

Note:

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

  • When the servo motor or air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.

    Click here

PROCEDURE

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

    1. E320974C02

      *a

      Front view of wire harness connector

      (to Air Conditioning Control Assembly)

      Disconnect the air conditioning control assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G20-5 (GND) - Body ground

      Always

      Below 1 Ω

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      G20-8 (IG+) - Body ground

      Power switch off

      Below 1 V

      G20-8 (IG+) - Body ground

      Power switch on (IG)

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

    1. Disconnect the G20 air conditioning control assembly connector.

    2. Disconnect the G81 air conditioning amplifier assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      G20-6 (LIN1) - G81-37 (LIN1)

      Always

      Below 1 Ω

      G20-6 (LIN1) or G81-37 (LIN1) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK AIR CONDITIONING CONTROL ASSEMBLY

    1. Replace the air conditioning control assembly.

      Click here

    2. When troubleshooting according to the DTC:

      1. Clear the DTCs.

        Click here

        Body Electrical > Air Conditioner > Clear DTCs

      2. Check for DTCs.

        Click here

        Body Electrical > Air Conditioner > Trouble Codes

        OK

        DTC B14B2 is not output.

    3. Check the air conditioning control assembly operates normally.

      Tip:

      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

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    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    Click here