Open in One Side of CAN Branch Line: Description

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

If some ECUs and sensors are 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 of the CAN branch lines

HINT.

If some ECUs and sensors repeatedly appear and disappear from the "CAN Bus Check" screen, communication between the normal ECUs (sensors) and 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 lines In this case, the CAN branch lines 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 lines)

SYMPTOM CHART

Symptom	Trouble Area
2 or more ECUs and/or sensors do not appear on the Techstream "CAN Bus Check" screen	One side of the CAN branch line is open Skid control ECU Steering angle sensor Yaw rate sensor ECM Gateway ECU Seat belt control ECU Distance control ECU Power steering ECU Center airbag sensor