Toyota CH-R Service Manual: Open in One Side of Bus 1 Branch Line

Toyota CH-R Service Manual / Networking / Can Communication System / Open in One Side of Bus 1 Branch Line

DESCRIPTION

When the CAN bus main lines are normal (no open, short to ground, short to +B or short between lines) and there is an ECU or sensor on the "Communication Bus Check" screen that is indicated as not communicating or whose connection status on the "Communication Bus Check" screen changes intermittently, an open in one of the wires of a CAN bus branch line is suspected.

HINT:

If there is an ECU or sensor whose connection status changes intermittently while checking the "Communication Bus Check" screen, there may be an open circuit in one of the wires of a branch line of an ECU or sensor in the bus. If an open occurs in one of the wires of a CAN branch line, it may interfere with the communication of other ECUs or sensors resulting in an incorrect state being displayed.

Symptom

Trouble Area

There is an ECU or sensor that is indicated as not communicating on the "Communication Bus Check" screen or whose connection status on the "Communication Bus Check" screen changes intermittently.

One side of CAN branch line is open, or output signals are incomplete.

  • Millimeter wave radar sensor assembly

    (w/ Toyota Safety Sense P)

  • Forward recognition camera

    (w/ Toyota Safety Sense P)

  • Blind spot monitor sensor LH

    (w/ Blind Spot Monitor System)

CAUTION / NOTICE / HINT

NOTICE:

  • 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.

    Click here

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

    DTC check procedure: Turn the blind spot monitor system on using the blind spot monitor main switch (ON/OFF switch), turn the cruise control main switch on, turn the LDA main switch on and then drive the vehicle at a speed of 40 km/h (25 mph) or more for approximately 52 seconds 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 as normal.

    Click here

PROCEDURE

1.

CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH LINE

(a) Based on the vehicle equipment and specifications, confirm the systems that use CAN communication.

Click here

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Using the Techstream, perform "CAN Bus Check".

Click here

CAN Bus Check

(f) Observe the screen for approximately 2 minutes to check for ECUs and sensors that are displayed as not communicating.

(g) Perform the inspection as specified in the Problem Symptoms Table for the ECUs or sensors that are not communicating.

NEXT

GO TO CORRESPONDING COMMUNICATION STOP MODE

    Check Bus 1 Line for Short to GND
    DESCRIPTION There may be a short circuit between one of the CAN bus lines and GND when there is no resistance between terminal 23 (CA1H) of the central gateway ECU (network gateway ECU) and termi ...

    Check Bus 2 Lines for Short Circuit
    DESCRIPTION There may be a short circuit between the CAN main bus lines and/or CAN branch lines when the resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network g ...

    Other materials:

    Toyota CH-R Service Manual > Rear View Monitor System: Problem Symptoms Table
    PROBLEM SYMPTOMS TABLE HINT: Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each sy ...

    Toyota CH-R Service Manual > Lighting (ext): Rear Side Marker Light Bulb
    Components COMPONENTS ILLUSTRATION *1 REAR COMBINATION LIGHT ASSEMBLY *2 REAR COMBINATION LIGHT COVER *3 REAR SIDE MARKER LIGHT BULB *4 REAR COMBINATION LIGHT SOCKET AND WIRE Removal REM ...

    Toyota C-HR (AX20) 2023-2026 Owner's Manual

    Toyota CH-R Owners Manual

    Toyota CH-R Service Manual

    © 2017-2026 Copyright www.tochr.net
    0.0131