Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000001FYRP
Model Year Start: 2019 Model: RAV4 Prod Date Range: [11/2018 - 08/2020]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): Open in One Side of Bus 4 Branch Line; 2019 - 2020 MY RAV4 [11/2018 - 08/2020]

Open in One Side of Bus 4 Branch Line

DESCRIPTION

If an ECU or sensor is not displayed on the "CAN Bus Check" screen of the Techstream and some ECUs and sensors repeatedly appear and disappear from the screen when the CAN main bus lines are normal (there is no open, short, short to +B or short to GND in the main bus lines), there may be an open circuit in either wire of one pair of CAN branch wires.

HINT:

If some ECUs and sensors repeatedly appear and disappear from the "CAN Bus Check" screen, communication between the normal ECUs (sensors) and the Techstream may be affected by the incomplete signals that are output from the ECU that has an open circuit in either of its CAN branch wires. In this case, the CAN branch wires for the ECUs and sensors that repeatedly appear and disappear from the screen are normal and the ECU that is not displayed on the screen may be the main cause of the problem (this ECU may have an open circuit in either of its CAN branch wires).

Symptom

Trouble Area

*1: w/ Occupant Classification System

*2: for AWD

*3: w/ Tire Pressure Warning System (Tire Inflation Pressure Display Function)

2 or more ECUs and/or sensors do not appear on the Techstream "CAN Bus Check" screen.

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

  • Steering sensor
  • Occupant detection ECU*1
  • Rack and pinion power steering gear assembly
  • Brake actuator assembly (skid control ECU)
  • 4WD ECU assembly*2
  • Tire pressure warning ECU and receiver*3

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

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 2019 - 2024 MY RAV4 [11/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING

  • 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 for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes 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 2019 MY RAV4 [11/2018 - 02/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2019 MY RAV4 [02/2019 - 10/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2020 MY RAV4 [10/2019 - 08/2020]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM

HINT:

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 FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE

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

Click here 2019 MY RAV4 [11/2018 - 02/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2019 MY RAV4 [02/2019 - 10/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2020 MY RAV4 [10/2019 - 08/2020]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM

(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 2019 MY RAV4 [11/2018 - 02/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2019 MY RAV4 [02/2019 - 10/2019]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM 2020 MY RAV4 [10/2019 - 08/2020]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM

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.

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