Multiport Fuel Injection (MFI)

DTC U0101: Transmission Control Module Time-Out

CAUTION:

- 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. (TCM 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 Conditions

- Battery positive voltage is between 10 and 16.5 volts.
Judgement Criterion

- Unable to receive TCM signals through the CAN bus line 4 seconds.

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.

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. CAN Bus Diagnostics Chart. 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 Diagnostic Trouble Code Chart.
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)Check that the other ECU performing CAN communication with TCM sets DTC No. U0101.
Controller Area Network (CAN).

(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. How to Cope With Intermittent Malfunctions.
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 (Refer to, Removal and Installation Removal and Replacement).
Then go to Step 6.
NO It can be assumed that this malfunction is intermittent of CAN bus line between ECM and TCM. How to Cope With Intermittent Malfunctions.
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.