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U0300




U0300 CAN COMMUNICATION DATA

Description

CAN (Controller Area Network) is a serial communication line for real-time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent malfunction detection ability.
Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independently). In CAN communication, control units are connected with 2 communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.


DTC Logic


DTC DETECTION LOGIC







DTC CONFIRMATION PROCEDURE


1. PREPARATION BEFORE WORK

If another "DTC CONFIRMATION PROCEDURE" occurs just before, turn ignition switch OFF and wait for at least 10 seconds, then perform the next test.
- GO TO 2.

2. CHECK DTC DETECTION

With CONSULT
1.Start the engine and wait for 5 seconds or more.
2.Check the DTC.
Is "U0300" detected?
YES- Go to .
NO- INSPECTION END


Diagnosis Procedure


1. CONTROL UNIT CHECK

Check the number of control units replaced before "U0300" is detected.
Is one control unit replaced?
YES- The specification of the control unit replaced may be incorrect. Check the part number and the specification.
NO- GO TO 2.

2. CONTROL UNIT CHECK

With CONSULT
1.Remove one of the control unit replaced.
2.Assemble the old control unit before replacement.
3.Turn ignition switch ON, and wait for 2 seconds or more.
4.Select "Self Diagnostic Results" in "TRANSMISSION".
Is "U0300"detected?
YES- Turn OFF the ignition switch and check other control units in the same manner.
NO- The specification of the control unit removed may be incorrect. Check the part number and the specification.