CAN COMMUNICATION SYSTEM Air Conditioning Amplifier Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Air Conditioning Amplifier Communication Stop Mode

  • "Air Conditioner" is not displayed on "Communication Bus Check" screen of intelligent tester

  • Applies to "Air Conditioning Amplifier Communication Stop Mode" in "DTC combination table"

  • Power source circuit of the air conditioning amplifier

  • Air conditioning amplifier branch wire or connector

  • Air conditioning amplifier

WIRING DIAGRAM

A017EAHE02
A017BXBE01

INSPECTION PROCEDURE

Note


  • Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.

  • After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If doors need to be opened in order to check the connectors, open the doors and leave them open.

Tech Tips


  • Operating the ignition switch, any other switches, or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below will help determine the cause of the malfunction.

PROCEDURE


  1. CHECK CAN BUS LINE FOR DISCONNECTION (AIR CONDITIONING AMPLIFIER BRANCH WIRE)


    1. Turn the ignition switch off.

    2. Disconnect the air conditioning amplifier connector.

    3. A017FS6E06

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D33-11 (CANH) - D33-12 (CANL) Ignition switch off 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

    OK

  2. CHECK HARNESS AND CONNECTOR (IG+, GND)


    1. Disconnect the air conditioning amplifier connector.

    2. A017FS6E07

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D33-14 (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
      D33-1 (IG+) - Body ground Ignition switch on (IG) 10 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here