AIR CONDITIONING SYSTEM, Diagnostic DTC:B14B2

DTC Code DTC Name
B14B2 Lost Communication with Front Panel LIN

DESCRIPTION

The air conditioning panel (heater control switch board) 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 panel (heater control switch board) is operated.

DTC No. DTC Detection Condition Trouble Area
B14B2 Lost communication with the air conditioning panel (heater control switch board).

  • Harness or connector between air conditioning control assembly and IG circuit

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

  • LIN communication system

  • Air conditioning panel (heater control switch board)

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A01ET2WE01

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING PANEL (HEATER CONTROL SWITCH BOARD) - IG CIRCUIT)


    1. Disconnect the I56 air conditioning panel (heater control switch board) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I56-2 (IG+) - Body ground Ignition switch off Below 1 V
      I56-2 (IG+) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING PANEL (HEATER CONTROL SWITCH BOARD) - BODY GROUND)


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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I56-6 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - AIR CONDITIONING PANEL (HEATER CONTROL SWITCH BOARD))


    1. Disconnect the I77 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
      I56-9 (LIN1) - I77-37 (LIN1) Always Below 1 Ω
      I56-9 (LIN1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE AIR CONDITIONING PANEL (HEATER CONTROL SWITCH BOARD)


    1. Replace the air conditioning panel (heater control switch board) Click here.

      Tech Tips

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

      OK
      Air conditioning panel (heater control switch board) 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

    B

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

    C

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    A

    END (HEATER CONTROL SWITCH BOARD WAS DEFECTIVE)