Vehicle electonic control need many informations of each module to reduce exhaust and increase convenience/safety by optimum control. The TCM can either receive data from the Engine Control Module or ABS control module, or it can send data to the ECM and ABSECM by using CAN communication. The CAN communicaton is one of the vehicle communications method, which is now widely used to transfer the vehicle data.
This code is set when PCM/TCM detected that worng message is sent or No reception of communication line.
Item
Detecting Condition
Possible Cause
DTC Strategy
CAN BUS OFF
Open or short in CAN line
PCM/TCM
Enable Conditions
Time after TCM turns on >0.5sec
Battery voltage > 10V
Input speed > 400rpm
Threshold value
BUS OFF or TIME OUT
Detecting Time
More than BUS OFF 1sec, TIME OUT 2sec & 2 D/C
Fail safe
Engine speed:3000rpm
Throttle : 50%
Engine torque : Max*0.7
* Inhibit TIME OUT happen at BUS OFF happen.
Fig 1) Wave form of "CAN COMMUNICATION"