Description of On-Board Diagnostics
DIAGNOSIS SYSTEMDESCRIPTION
a. As shown in the illustration, each ECU of the vehicle is connected by communication bus and transmit each signal by communication. This communication bus is self-diagnosed by the body ECU and memorizes DTC when it detects a communication stop to ECU or communication bus +B short or GND short. There is a possibility that body ECU cannot self-diagnose accurately unless it works normally. Please note that the troubleshooting of the body electrical system should be done after confirming the body ECU and open door indicator to work normally by 2 "BASIC INSPECTION", which is described later.
b. If DTC of ECU communication stop is indicated, there is a possibility of connector disconnection or 2 communication buses open. It will not become abnormal with only 1 communication bus open.
c. If 2 communication buses are open at the positions as shown in the illustration, DTC of ECU communication stop between those 2 buses will be indicated.