General Information
Body Control Module
B1603 CAN Bus Off - General Information
Component Location
General Description
This DTC sets when a communication error between SJB and other control units occur.
** Body CAN communication Control Units : BCM(Body Control Module), CLU(Cluster), SMK(Smart Key), SJB(Smart Junction Box), PSM(Power Seat Module).
CAN (Controller Area Network) : CAN is a serial bus type communication which links control units.
LIN (Local Interconnect Network) : LIN is serial communication type which is used in electrical control system. (This is less expensive)
DTC Description
This DTC sets when a communication error between SJB and other control units occur.
(** Control Units : BCM(Body Control Module), CLU(Cluster), SMK(Smart Key), SJB(Smart Junction Box), PSM(Power Seat Module)
Case1: After short between CAN Low Line and High Line, short to ground together.
Case2: After short between CAN Low Line and High Line, short to power together.
** This code sets when the module is unable to transmit data on the CAN Line. It may be possible to receive data on the CAN Line.
This code reports "BUS OFF" status when a data transmit error count is over 255. The purpose is to verify the status of CAN controller and CAN communication line when error is detected.
Depending on operation condition, some modules which are connected to the CAN line may not detect B1603.
Also, B1602 coincides with B1603 at all times.
CAUTION:
Difference between CAN ERROR and CAN BUS ERROR
CAN Error : MIL On, CAN Bus Error : No MIL
DTC Detecting Condition
Diagnostic Circuit Diagram
Signal Waveform & Data
Fig.1) CAN Low/High Signal Waveform
Fig.2) CAN BUS VOLTAGE LEVEL (LOW SPEED CAN)