Can communication

Open in One Side of CAN Branch Line

4steps
~24min
2/5difficulty
Done 0 of 4

DESCRIPTION

If 2 or more ECUs and/or sensors do not appear on the intelligent tester "Communication Bus Check" screen, one side of the CAN branch wire may be open. (One side of the CAN-H [branch wire] / CAN-L [branch wire] of the ECU and/or sensor is open.)

Symptom

Trouble Area

2 or more ECUs and/or sensors do not appear on the intelligent tester "Communication Bus Check" screen.
  • One side of the CAN branch wire is open
  • Skid control ECU
  • Steering angle sensor
  • Yaw rate sensor
  • Distance control ECU

WIRING DIAGRAM

WIRING DIAGRAM
WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

  • Turn the ignition switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
  • After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT: Perform the following inspection for the ECUs (sensors) which are not displayed on the intelligent tester. If the malfunction cannot be identified, then perform the following inspections for the ECUs (sensors) connected to CAN communication.

1 CHECK FOR OPEN IN ONE SIDE OF CAN BRANCH WIRE

  1. Confirm the systems (ECUs and sensors), which use CAN communication, equipped on the vehicle. (See page CA-17)
  2. Using the intelligent tester, select and perform "Communication Bus Check". (See page CA-17) [*1]
  3. Disconnect the connectors from the ECUs or sensors that are not displayed on the screen. [*2]
  4. Check that only the ECUs and sensors from which the connectors were disconnected in the previous step are not displayed on the "Communication Bus Check" screen. [*3]

HINT: If any ECUs or sensors, other than those from which the connectors were disconnected in the previous step, are not displayed on the "Communication Bus Check" screen, reconnect the disconnected connectors and repeat the procedures [*1], [*2], and [*3].

(e) Perform the communication stop mode check for the ECUs and sensors which correspond to the disconnected connectors.

GO TO CORRESPONDING COMMUNICATION STOP MODE

Test yourself

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