AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System), Diagnostic DTC:B14B3

DTC Code DTC Name
B14B3 Lost Communication with Rear Panel LIN

DESCRIPTION

The No. 2 air conditioning control assembly communicates with the air conditioning amplifier assembly via LIN communication.

If the LIN communication system is malfunctioning, the air conditioning amplifier assembly does not operate even if the No. 2 air conditioning control assembly is operated.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B14B3 Lost Communication with Rear Panel LIN Lost communication with No. 2 air conditioning control assembly

  • Harness or connector between No. 2 air conditioning control assembly and IG power source

  • Harness or connector between No. 2 air conditioning control assembly and body ground

  • LIN communication system

  • No. 2 air conditioning control assembly

  • Air conditioning amplifier assembly

Memorized

(10 sec. or more)*1

WIRING DIAGRAM

A002C93E05
*1 from IG1 NO. 2 Relay
*2 No. 2 Air Conditioning Control Assembly
*3 Air Conditioning Amplifier Assembly
*4 LIN Communication Line

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (NO. 2 AIR CONDITIONING CONTROL ASSEMBLY - IG POWER SOURCE)


    1. Disconnect the U1 No. 2 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
      U1-6 (IG) - Body ground Ignition switch off Below 1 V
      U1-6 (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 (NO. 2 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
      U1-7 (E) - 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 - NO. 2 AIR CONDITIONING CONTROL ASSEMBLY)


    1. Disconnect the F81 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
      U1-12 (RLIN) - F81-16 (RLIN) Always Below 1 Ω
      U1-12 (RLIN) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE NO. 2 AIR CONDITIONING CONTROL ASSEMBLY


    1. Replace the No. 2 air conditioning control assembly.

      Click here

      Tech Tips

      Since the No. 2 air conditioning control assembly cannot be inspected while it is removed from the vehicle, replace the No. 2 air conditioning control assembly with a new or known good one and check that the condition returns to normal.

      OK
      No. 2 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 (NO. 2 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