CAN COMMUNICATION SYSTEM Air Conditioning Amplifier Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Air Conditioning Amplifier Communication Stop Mode

Any of the following conditions are met:


  • Communication stop for "Air Conditioning Amplifier" is indicated on the "Communication Bus Check" screen of the GTS.

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  • Communication stop history for "Air Conditioning Amplifier" is indicated on the "Communication Bus Check (Detail)" screen of the GTS. (The Lost Communication Time value for "Air Conditioning Amplifier" is 6 or more.)

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  • Communication system DTCs (DTCs that start with U) that correspond to "Air Conditioning Amplifier Communication Stop Mode" in "DTC Combination Table" are output.

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  • Air conditioning amplifier assembly branch line or connector

  • Power source circuit of air conditioning amplifier assembly

  • Air conditioning amplifier assembly ground circuit

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A001Y7DE01

CAUTION / NOTICE / HINT

Note


  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

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  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

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  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch ON and wait at least approximately 20 seconds.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

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

Tech Tips


  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.

  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE


  1. CHECK VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      w/ Top-mounted Air Conditioner Pressure Sensor A
      w/ Side-mounted Air Conditioner Pressure Sensor B

    B
    A
  2. CHECK FOR OPEN IN CAN BUS LINES (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH LINE)


    1. Disconnect the cable from the negative (-) battery terminal.

    2. Disconnect the air conditioning amplifier assembly connector.

    3. A001U9GC43
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F72-9 (CANH) -F72-10 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Result
      OK
      NG

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    1. A001U9GC46
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F72-29 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
    2. Reconnect the cable to the negative (-) battery terminal.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      F72-1 (B) - Body ground Always 11 to 14 V
      F72-5 (IG+) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result
      OK
      NG

    OK
    NG
  4. CHECK FOR OPEN IN CAN BUS LINES (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH LINE)


    1. Disconnect the cable from the negative (-) battery terminal.

    2. Disconnect the air conditioning amplifier assembly connector.

    3. A005OGBC15
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F73-11 (CANH) -F73-12 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Result
      OK
      NG

    NG
    OK
  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    1. A001TK9C16
      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F73-4 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
    2. Reconnect the cable to the negative (-) battery terminal.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      F73-1 (B) - Body ground Always 11 to 14 V
      F73-2 (IG+) - Body ground Ignition switch ON 11 to 14 V
      Result
      Result
      OK
      NG

    OK
    NG