Transmission Control System

DTC U1000 CAN COMMUNICATION LINE

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 independent). 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.

On Board Diagnosis Logic
- This is an OBD-II self-diagnostic item.
- Diagnostic trouble code U1000 CAN COMM CIRCUIT with CONSULT-III is detected when TCM cannot communicate to other control units.

Possible Cause
Harness or connectors
(CAN communication line is open or shorted.)

DTC Confirmation Procedure

NOTE: If DTC Confirmation Procedure has been previously performed, always turn ignition switch OFF and wait at least 10 seconds before performing the next test.

After the repair, touch ERASE on SELF-DIAG RESULTS and then perform the following procedure to confirm the malfunction is eliminated.

WITH CONSULT-III
1. Turn ignition switch ON.
2. Select DATA MONITOR mode for TRANSMISSION with CONSULT-III.
3. Start engine and wait for at least 6 seconds.
4. If DTC is detected, go to "Diagnostic Procedure" below.

WITH GST
Follow the procedure WITH CONSULT-III.

CVT-CAN-01:

Wiring Diagram - CVT - CAN

TCM TERMINALS AND REFERENCE VALUES
Refer to CVT-49, "TERMINALS AND REFERENCE VALUES FOR TCM". Pinout Values and Diagnostic Parameters

Diagnostic Procedure
1. CHECK CAN COMMUNICATION CIRCUIT

WITH CONSULT-III
1. Turn ignition switch ON and start engine.
2. Select SELF-DIAG RESULTS mode for TRANSMISSION with CONSULT-III.
Is any malfunction of the U1000 CAN COMM CIRCUIT indicated?
YES >> Print out CONSULT-III screen, go to LAN section. Refer to LAN-23, "CAN System Specification Chart". Testing and Inspection
NO >> INSPECTION END