CAN COMMUNICATION SYSTEM Open in One Side of CAN Sub Bus Line

DESCRIPTION

If "Engine", "ECT (*1)" and "Air Conditioner" do not appear on the intelligent tester's "Communication Bus Check" screen, one side of CAN sub bus line may be open (either CAN-H or CAN-L of the CAN sub bus lines) or the ECM may be defective.

Symptom Trouble Area
"Engine", "ECT (*1)" and "Air Conditioner" do not appear on the intelligent tester's "Communication Bus Check" screen.

  • One side of CAN sub bus line is open

  • CAN J/C

  • Air conditioning amplifier

  • ECM

Tech Tips

*1: Applicable only to automatic transmission vehicles with 1KD-FTV or 2KD-FTV engine.

WIRING DIAGRAM

A01BHQDE01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR AN OPEN IN ONE SIDE OF THE CAN SUB BUS LINE (AIR CONDITIONING AMPLIFIER SUB BUS LINE)


    1. Turn the ignition switch off.

    2. A01BFF5E06

      Disconnect the air conditioning amplifier sub bus line connector (H3) from the CAN J/C.

      Note


      • Before disconnecting the connector, make a note of where it is connected.

      • Reconnect the connector to its original position.

    3. Turn the ignition switch on.

    4. Select "Communication Bus Check"on the intelligent tester. Click here

      Result
      Go to step Result
      A "Engine", "ECT (*1)" and "A/C" are not displayed.
      B "A/C" is not displayed ("Engine" and "ECT (*1)"are displayed).

      Tech Tips

      *1: Applicable only to automatic transmission vehicles with 1KD-FTV or 2KD-FTV engine.


    B

    CONNECT CONNECTOR Click here

    A

  2. INSPECT CAN J/C


    1. Turn the ignition switch off.

    2. Disconnect the all connectors (H3), (H4) and (H5) from the CAN J/C.

      Note


      • Before disconnecting the connectors, make a note of where it is connected.

      • Reconnect the connectors to its original position.

    3. A01BD9HE01

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

      Standard resistance
      Tester Connection Condition Specified value
      CANH - CANL IG switch OFF 108 to 132 Ω

    NG

    REPLACE CAN J/C

    OK

    REPLACE ECM

  3. CONNECT CONNECTOR


    1. Reconnect the air conditioning amplifier sub bus line connector (H3) to the CAN J/C.


    NEXT

  4. CHECK FOR AN OPEN IN ONE SIDE OF THE CAN SUB BUS LINE (AIR CONDITIONING AMPLIFIER SUB BUS LINE)


    1. A01BHX5E02

      Turn the ignition switch off.

    2. Disconnect the air conditioning amplifier connector (H18).

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

      Standard resistance
      Tester Connection Condition Specified Value

      H18-10 (CANH) -

      H18-11 (CANL)

      		 IG switch OFF 54 to 69 Ω

    NG

    REPAIR OR REPLACE AIR CONDITIONING AMPLIFIER SUB BUS LINE OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER