AUTOMATIC TRANSAXLE SYSTEM ECU Power Source Circuit

DESCRIPTION

When the ignition switch is turned ON, voltage from the MREL terminal of the ECM is applied to the EFI MAIN relay. This causes the contacts of the EFI MAIN relay to close, which supplies power to terminal +B of the TCM.

WIRING DIAGRAM

Refer to DTC U0100 Click here.

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK TCM (TCM - BODY GROUND)


    1. A01IUNZE20
      Text in Illustration
      *a

      Front view of wire harness connector

      (to TCM)

      Disconnect the TCM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C29-8 (E1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - TCM)


    1. Remove the EFI MAIN relay from the engine room No. 1 relay block.

    2. Disconnect the C29 TCM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Engine room No. 1 relay block EFI MAIN relay terminal 3 - C29-18 (+B) Always Below 1 Ω
      Engine room No. 1 relay block EFI MAIN relay terminal 3 or C29-18 (+B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    GO TO ECD SYSTEM (ECM POWER SOURCE CIRCUIT) Click here