Open in One Side of CAN Sub Bus Line

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

DESCRIPTION

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





WIRING DIAGRAM















HINT
* The following is the troubleshooting procedures of an open in either CANH or CANL of the ECU A (SENSOR A).
* Perform the following inspection for the ECUs (sensors) which are not displayed on the Techstream. If malfunction cannot be identified, then perform the following inspections for the ECUs (sensors) connected to the CAN communication.
PROCEDURE

1. CHECK FOR AN OPEN IN ONE SIDE OF THE CAN SUB BUS LINE

(a) Disconnect the connector with terminals CANH and CANL of the ECU A (SENSOR A).





(b) Select "CAN Bus Check" on the Techstream.

Result:





B -- CHECK FOR MALFUNCTIONING ECU (SENSOR) BY CONNECTING CONNECTOR OF ECU A
A -- Continue to next step.

2. CHECK FOR AN OPEN IN ONE SIDE OF THE CAN SUB BUS LINE

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





Standard resistance:

54 to 69 Ohms

NG -- REPAIR OR REPLACE ECU A SUB BUS LINE OR CONNECTOR

OK -- REPLACE ECU A (SENSOR A)