CAN COMMUNICATION SYSTEM Air Conditioning Amplifier Communication Stop Mode

DTC Code DTC Name
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 the CAN Bus Check screen of the GTS

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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

C275812E03
C275811E03

CAUTION / NOTICE / HINT

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

  • DTC check procedure: Turn the ignition switch to ON and wait at least 20 seconds, and then drive the vehicle at a speed of 20 km/h (12 mph) or more.

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

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Tip:
  • 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 may help determine the cause of the malfunction.

PROCEDURE

  1. CHECK VEHICLE TYPE

    1. Check vehicle type.

    Result

    Result

    Result

    Proceed to

    w/ Automatic Air Conditioning System

    A

    w/ Manual Air Conditioning System

    B

    B

    CHECK FOR OPEN IN CAN BUS LINES (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH LINE)Click here

    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. C256258C06

      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Disconnect the E28 air conditioning amplifier assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E28-11 (CANH) - E28-12 (CANL)

      Cable disconnected from negative (-) battery terminal

      54 to 69 Ω

    Result

    Result

    Result

    OK

    NG

    NG

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY)

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

    1. C256258C07

      *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

      E28-14 (GND) - Body ground

      Cable disconnected from negative (-) battery terminal

      Below 1 Ω

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

    3. C256258C08

      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E28-1 (IG+) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Result

    Result

    OK

    NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

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

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

    2. E218543C13

      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Disconnect the E62 air conditioning amplifier assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E62-8 (CANH) - E62-9 (CANL)

      Cable disconnected from negative (-) battery terminal

      54 to 69 Ω

    Result

    Result

    Result

    OK

    NG

    NG

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY)

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

    1. E218543C14

      *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

      E62-23 (GND) - Body ground

      Cable disconnected from negative (-) battery terminal

      Below 1 Ω

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

    3. E218543C17

      *a

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E62-1 (IG+) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Result

    Result

    OK

    NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)