CAN COMMUNICATION SYSTEM Air Conditioning Amplifier Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Air Conditioning Amplifier Communication Stop Mode

Either condition is met:


  • "Air Conditioning Amplifier" is not displayed on "Bus Check".

  • "Air Conditioning Amplifier Communication Stop Mode" in "DTC Combination Table" applies.

  • Power source or inside air conditioning amplifier assembly

  • Air conditioning amplifier assembly CAN branch wire or connector

  • Air conditioning amplifier assembly

WIRING DIAGRAM

B007UHBE67

INSPECTION PROCEDURE

Note

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

Tech Tips

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      For vehicles with an airbag system:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.


    NEXT

  2. CHECK FOR OPEN IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY CAN BRANCH WIRE)


    1. B007R1DE03
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Disconnect the air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H18-10 (CANH) - H18-11 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY CAN BRANCH WIRE OR CONNECTOR (CANH, CANL)

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BATTERY AND BODY GROUND)


    1. B007R1DE05
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Connect the cable to the negative (-) battery terminal.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H18-29 (GND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      H18-40 (B) - Body ground Always 11 to 14 V
      H18-20 (IG+) - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here