CAN communication is a parallel circuit to interchange information among each units. CAN communication can share much information with units more faster and more efficiently by using specified language.
CAN-High line is twisted with CAN-Low line as a purpose in preventing from a noise.
ITM-ECU performs active control by sharing signals of engine RPM, APS, shift position, torque reduction.
This code related to communication line between ECU and 4WD ECM( = TCCU : Transfer Case Control Unit) is set when CAN signal from ECU can't received for more than 1sec or ECU internal error occur.
If failure is detected 4WD ECM prohibits the ITM control and cuts the current to control coil.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
TCU-ITM communication line or ECU side malfunction. (A/T only) |
•
CAN HIGH/LOW circuit open/short.
•
Faulty TCU.
•
Faulty 4WD ECM(TCCU). |
Enable Conditions |
•
IG KEY "ON" , ENGINE "ON " | |
Threshold Value |
•
Loss of TCU1 message for greater than 1 second, and a fault will be set. This fault applies to an automatic transmission only. | |
Diagnostic Time |
•
1 sec. | |
MIL on condition |
•
0.5 sec. | |
Fail Safe |
•
Trans gear set to first, engine torque set to zero, ECU will not send current to the clutch coil. |
Fig.1) CAN Signal : high & low
