CLEARANCE SONAR SYSTEM Speed Signal Circuit

DESCRIPTION

The clearance warning ECU receives the vehicle speed signal from the combination meter.

Tech Tips


  • A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter. The signal is changed to a pulse signal at the transistor in the combination meter. Each ECU controls the respective system based on the pulse signal.

  • If a short occurs in an ECU, all systems in the diagram below will not operate normally.

WIRING DIAGRAM

A01BFFWE01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK OPERATION OF SPEEDOMETER


    1. Drive the vehicle and check if the function of the speedometer in the combination meter is normal.

      OK
      Actual vehicle speed and the speed indicated on the speedometer are the same.

      Tech Tips

      The vehicle speed sensor is functioning normally when the indication on the speedometer is normal.


    NG

    CHECK COMBINATION METER

    OK

  2. INSPECT CLEARANCE WARNING ECU


    1. A01BG69E01

      Disconnect the clearance warning ECU connector H33.

    2. Measure voltage.


      1. Jack up either one of the drive wheels.

      2. Move the shift lever to the neutral position.

      3. Turn the ignition switch to the ON position.

      4. Measure the voltage between terminal SPD of the clearance warning ECU and body ground when the drive wheels are turned slowly.

        A01BGZNE01
        OK
        Voltage pulses as shown.

    OK

    REPLACE CLEARANCE WARNING ECU

    NG

  3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - CLEARANCE WARNING ECU)


    1. A01BFGPE01

      Disconnect the combination meter H20 connector.

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

      Resistance

      Tester connection

      (Symbols)

      		 Condition Specified condition

      H33-25 (SPD) -

      H20-9 (+S)

      		 Ignition switch off Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER AND EACH ECU - BODY GROUND)


    1. A01BGNJE01

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

      Resistance

      Tester connection

      (Symbols)

      		 Condition Specified condition

      H33-25 (SPD) -

      Body ground

      		 Ignition switch off 10 kΩ or higher

      Tech Tips

      If the resistance between terminal SPD and body ground is less than 10 kΩ, there may be a short in a wire harness, connector, or ECU.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR OR CHECK EACH ECU

    OK

    REPLACE COMBINATION METER