Precautions On How To Repair The Can Bus Lines

Precautions on how to repair the CAN bus lines 

• If the CAN_L or CAN_H line on the main bus line or sub-bus line is repaired, replace all the twisted wires between the end connectors. If the wiring harness is partially repaired, or only CAN_L or CAN_H line is repaired, noise suppression is deteriorated, causing a communication error.
  Fig 1: Identifying CAN Bus Lines Added Wire

  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
• If the connector or wire on the main bus line or the sub-bus wire is replaced, the strand end of the twisted wire should be within 10 cm (4 inches) from the connector. If it exceeds 10 cm (4 inches), twist the wiring harness just like the original twisted wire. If the strand end exceeds 10 cm (4 inches), noise suppression is deteriorated, causing a communication error.
  Fig 2: Identifying Strand End Of Twisted Wire From Connector

  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
• If a sub-bus line is repaired, splice a new wire directly into the main bus line. If a new wire is spliced into the sub-bus line, which is connected to another device, the CAN communication will be disabled.
  Fig 3: Identifying Main & Sub Bus Lines

  Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Precautions on how to repair the terminator resistor 

If one-side of the terminator resistors is broken, the CAN communication will continue, although noise suppression is deteriorated. In this case, no DTC may be set. Check the system regardless of whether a DTC is set or not. If damage is found, replace the terminator resistor.