TC-SST-ECU Timeout
DTC U0101: TCM Time-outCAUTION:
- If the ECM output the DTC U0101, make sure to diagnose the CAN bus line.
- Before replacing the ECU, make sure that the communication circuit is operating normally.
DESCRIPTIONS OF MONITOR METHODS
There is no data from TCM for the specified time. (Meter also detect communication error with ECM.)
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)
- Not applicable
Sensor (The sensor below is determined to be normal)
- Not applicable
DTC SET CONDITIONS
Logic Flow Chart:
Check Condition
- Battery positive voltage is between 10 and 16.5 volts.
Judgement Criterion
- Unable to receive TCM signals through the CAN bus line for 4 seconds.
COMMENT
Current Trouble
- Some of the possible causes are a harness or connector damage between the ECM and the TCM on the CAN bus line, a failure in the TCM power supply system, a failure in the TCM, or a failure in the ECM.
Past Trouble
- Proceed to troubleshoot based on a harness or connector damage on the CAN bus line between the ECM and TCM, and a failure in the TCM power supply system.
NOTE: If a malfunction occurred in the past, a failure cannot be discovered through the M.U.T. - III CAN bus diagnosis even if there might be a problem with the CAN bus. Furthermore, it is possible to narrow down the areas of the possible failures from the DTCs that are output by the ECUs, which are communicating on the CAN bus.
OBD-II DRIVE CYCLE PATTERN
None.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- CAN line harness damage or connector damage.
- TCM failed.
- ECM failed.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
STEP 1. Using scan tool MB991958, diagnose CAN bus line.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Diagnose CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line normal?
YES : Go to Step 2.
NO : Repair the CAN bus line. Then go to Step 6.
STEP 2. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. Read the TCM-DTC.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CVT-DTC set?
YES : Refer to Diagnostic Trouble Code Descriptions.
NO : Go to Step 3.
STEP 3. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. Read the ABS-DTC and ETACS-DTC.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?
YES : Go to Step 4.
NO : Go to Step 5.
STEP 4. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. After the MFI-DTC has been deleted, read the MFI-DTC again.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?
YES : Replace the TCM. Then go to Step 6.
NO : It can be assumed that this malfunction is intermittent of CAN bus line between ECM and TCM.
STEP 5. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. After the MFI-DTC has been deleted, read the MFI-DTC again.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?
YES : Replace the ECM. When the ECM is replaced,register the ID code. Then go to Step 6.
NO : It can be assumed that this malfunction is intermittent of CAN bus line between ECM and TCM.
STEP 6. Using scan tool MB991958, read the diagnostic trouble code (DTC).
1. Turn the ignition switch to the "ON" position.
2. After the MFI-DTC has been deleted, read the MFI-DTC again.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?
YES : Retry the troubleshooting.
NO : The inspection is complete.