LAN System Condition of Error Detection

LAN System: Condition of Error Detection

DTC (e.g. U1000 and U1001) of CAN communication is indicated on DTC check on SDT if a CAN communication signal is not transmitted or received between units for 2 seconds or more.

CAN Communication System Error

- CAN communication line open (CAN-H, CAN-L, or both)
- CAN communication line short (ground, between CAN communication lines, other harnesses)
- Error of CAN communication control circuit of the unit connected to CAN communication line

When DTC of CAN Communication is Indicated Even Though CAN Communication System is Normal

- Removal/installation of parts: Error may be detected when removing and installing CAN communication unit and related parts while turning the ignition switch ON. (A DTC except for CAN communication may be detected.)
- Fuse blown out (removed): CAN communication of the unit may cease.
- Voltage drop: Error may be detected if voltage drops due to discharged battery when turning the ignition switch ON (Depending on the control unit which carries out CAN communication).
- Error may be detected if the power supply circuit of the control unit, which carries out CAN communication, malfunctions (Depending on the control unit which carries out CAN communication).
- Error may be detected if reprogramming is not completed normally.

CAUTION:

CAN communication system is normal if DTC of CAN communication is indicated on DTC check of SDT under the above conditions. Erase the memory of the self-diagnosis of each unit.