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 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)*

WIRING DIAGRAM

B004PHXE22

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 F52 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
      F52-8 (IG+) - Body ground Power switch on (IG) 11 to 14 V
      F52-8 (IG+) - Body ground Power switch off Below 1 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
      F52-1 (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 F58 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
      F52-6 (LIN1) - F58-14 (LIN1) Always Below 1 Ω
      F52-6 (LIN1) or F58-14 (LIN1) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Reconnect the F58 air conditioning amplifier assembly connector.

    2. Turn the power switch on (IG).

    3. B004P5ZN03

      Connect an oscilloscope to terminals F58-14 (LIN1) and F58-4 (GND) of the air conditioning amplifier assembly and check the waveform.

      OK
      Waveform is similar to that shown in the illustration.
      Item Content
      Tool Setting 2 V/DIV., 20 ms./DIV.
      Vehicle Condition Power switch on (IG)
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    OK

  5. INSPECT AIR CONDITIONING CONTROL ASSEMBLY


    1. Reconnect the F52 air conditioning control assembly connector.

    2. Turn the power switch on (IG).

    3. B004P9SC02
      *a

      Component with harness connected

      (Air Conditioning Control Assembly)

      Connect an oscilloscope to terminals F52-6 (LIN1) and F52-1 (GND) of the air conditioning control assembly and check the waveform.

      OK
      Waveform is similar to that shown in the illustration.
      Item Content
      Tool Setting 2 V/DIV., 20 ms./DIV.
      Vehicle Condition Power switch on (IG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING CONTROL ASSEMBLY Click here