Automatic Transmission
DTC U0001: Can Bus Off
DESCRIPTIONS OF MONITOR METHODS
- Open circuit or short circuit occurs in the CAN communication line (CAN_H, CAN_L).
- The communication becomes impossible with all the control modules for 0.5 seconds or more.
MONITOR EXECUTION
- Continuous
MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)
Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- P0712: Malfunction of the transmission fluid temperature sensor (Short circuit)
- P0715: Malfunction of the Input shaft speed sensor system
- P0731: Malfunction of the 1st gear incorrect ratio
- P0732: Malfunction of the 2nd gear incorrect ratio
- P0733: Malfunction of the 3rd gear incorrect ratio
- P0734: Malfunction of the 4th gear incorrect ratio
- P0735: Malfunction of the 5th gear incorrect ratio
- P0729: Malfunction of the 6th gear incorrect ratio
- P0741: Malfunction of the Malfunction of the Torque converter clutch system (Stuck off)
- P0742: Malfunction of the Torque converter clutch system (Stuck on)
- P0846: Malfunction of the 2-6 brake pressure switch system
- P0876: Malfunction of the High clutch pressure switch system
- P0988: Malfunction of the Low-reverse brake pressure switch system
- P0893: Malfunction of the Interlock detection
- P1705: Malfunction of the Throttle position sensor information (engine)
- P1706: Malfunction of the Accelerator pedal position information
- P1773: Malfunction of the ABS information (ASC)
- U0100: Malfunction of the ECM time-out
Sensor (The sensor below is determined to be normal)
- Transmission fluid temperature sensor
- Input shaft speed sensor
LOGIC FLOW CHARTS (Monitor Sequence)
DTC SET CONDITIONS
Check Conditions
- TCM is started: more than 1.05 seconds.
- A/T control relay voltage: 10 volts or more.
- A/T control relay voltage: 16 volts or less.
Judgement Criteria
- CAN communication: fail.
OBD-II DRIVE CYCLE PATTERN
With the ignition switch ON, maintain the status for 10 seconds or more.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
- Malfunction of the CAN circuit
- Malfunction of the TCM
- Damaged harness or connector
- Malfunction of the CAN system module
DIAGNOSIS
STEP 1. Check the CAN communication system malfunction.
- Check that the CAN system-related DTC code other than U0001 is set.
- Check that the CAN-related DTC is set with other relevant modules.
Q. Is the check result normal?
YES Go to Step 2.
NO Repair or replace the failure section.
STEP 2. Check the CAN communication lines.
[C-38 TCM connector (vehicle side, disconnected)]
Between C-38 terminal No. 10, 11 and the CAN communication lines of other ECU: Continuity exists.
When the continuity check result is OK, check that the wiring harness is not shorted to the body and other wiring harness. Also, check for a short circuit between the twisted pair cables.
Q. Is the check result normal?
YES Go to Step 3.
NO Repair or replace the failure section.
STEP 3. Check the relevant ECUs and the TCM connector pin terminal, and the connection status.
Q. Is the check result normal?
YES Repair or replace the failure section.
NO Replace the TCM.