ECD SYSTEM (w/o DPF), Diagnostic DTC:U0101

DTC Code DTC Name
U0101 Lost Communication with TCM

DESCRIPTION

The ECM intercommunicates with the TCM through the Controller Area Network (CAN).

If there is a problem in this intercommunication, the ECM sets the DTC.

DTC No. DTC Detection Condition Trouble Area
U0101
  • Following conditions are met for 1.25 seconds (1 trip detection logic):


    1. Ignition switch ON

    2. Battery voltage 10.5 V or more

    3. No intercommunication between ECM and TCM


  • ECM

  • TCM

  • ECM to TCM circuit

WIRING DIAGRAM

A003F9OE03

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC U0101)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    4. Read the DTCs.

      Result
      Result Proceed to
      U0101 is output A
      U0101 and other DTCs are output B

      Tech Tips

      If any DTCs other than U0101 are output, troubleshoot those DTCs first.


    B
    A
  2. INSPECT TCM


    1. A003C8EE30
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to TCM)

      Disconnect the TCM connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      O3-5 (BATT) - O1-1 (E1) Ignition switch ON 11 to 14 V
    3. Reconnect the TCM connector.


    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (TCM - ECM)


    1. Disconnect the ECM connector.

    2. Disconnect the TCM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      D98-40 (CAN+) - O3-21 (CAN+) Always Below 1 Ω
      D98-63 (CAN-) - O3-20 (CAN-) Always Below 1 Ω
      D98-40 (CAN+) or O3-21 (CAN+) - Body ground Always 10 kΩ or higher
      D98-63 (CAN-) or O3-20 (CAN-) - Body ground Always 10 kΩ or higher
    4. Reconnect the TCM connector.

    5. Reconnect the ECM connector.


    NG
    OK
  4. REPLACE ECM


    NEXT
  5. CHECK WHETHER DTC OUTPUT RECURS (DTC U0101)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    4. Read the DTCs.

      Result
      Result Proceed to
      No DTC is output A
      U0101 is output B

    B
    A