STOP AND START SYSTEM STA Signal Circuit

DESCRIPTION

While the engine is being cranked, a starter operation request signal is sent to terminal STA of the ECM.

Tech Tips

If there is an open in the STA circuit of the ECM, stop and start control will be prohibited after the third time the engine is started by stop and start control.


  • Stop and start control will be prohibited until the engine switch is turned off.

  • The MIL will not illuminate.

  • If there is an open in the STA circuit of the ECM, the engine can still be started using the engine switch, as the ECM also receives the starter operation request signal from the engine stop and start ECU via CAN communication. (Stop and start control is prohibited as the reliability of the signal sent via CAN communication cannot be assured while the voltage drops during operation of the starter assembly.)

A01W4ECE05

WIRING DIAGRAM

A01W2COE05

PROCEDURE


  1. READ VALUE USING GTS (ENGINE STARTER SIGNAL)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Stop and Start / Data List / Engine Starter Signal.

    5. Check the Data List when the engine switch is operated.

      OK
      Engine switch Engine Starter Signal
      ON OFF
      START ON

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ST NO. 2 RELAY)


    1. Disconnect the A75 ECM connector.

    2. Remove the ST NO. 2 relay from engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A75-29 (STA) - ST NO. 2 relay holder 2 Always Below 1 Ω

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR