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

B14B2

Lost Communication with Front Panel LIN

Lost communication with air conditioning control assembly

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

  • 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

  • *1: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.

WIRING DIAGRAM

E226613E28

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

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

    1. Disconnect the E71 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

      E71-8 (IG+) - Body ground

      Ignition switch off

      Below 1 V

      E71-8 (IG+) - Body ground

      Ignition switch ON

      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 - BODY GROUND)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E71-5 (GND) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

    1. Disconnect the E28 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

      E71-6 (LIN1) - E28-37 (LIN1)

      Always

      Below 1 Ω

      E71-6 (LIN1) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE AIR CONDITIONING CONTROL ASSEMBLY

    1. Replace the air conditioning control assembly.

      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

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY