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 ignition 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 ignition or starter switch assembly (w/o Entry and Start System) or push start switch assembly (w/ Entry and Start System), 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.)

A01SHC6E05

WIRING DIAGRAM

A01SHTYE08

PROCEDURE


  1. READ VALUE USING GTS (STARTER SIGNAL)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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


      Powertrain > Engine and ECT > Data List
      Tester Display
      Starter Signal

    5. Read the values displayed on the GTS when the engine starts.

      OK
      Tester Display Condition Normal Condition
      Starter Signal Ignition switch ON OFF
      Engine start ON
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (ECM - ST NO. 2 RELAY)


    1. Disconnect the G85 ECM connector.

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

    3. Disconnect the G126 engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G85-22 (STA) - ST NO. 2 relay terminal 2 Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR