STOP AND START SYSTEM STA Signal Circuit

DESCRIPTION

The engine stop and start ECU utilizes the starter delay circuit to activate the start pinion activation relay (ST/MGC relay), then the starter motor activation relay (ST2 relay), and then operates the starter.

WIRING DIAGRAM

Refer to B22C0 Click here

Refer to P0562 Click here

Refer to P0617 Click here

CAUTION / NOTICE / HINT

Note


  • Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU Click here.

  • After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU Click here.

  • After replacing the engine stop and start ECU or airbag sensor assembly, perform deceleration sensor zero point clear and calibration Click here.

  • After replacing the starter assembly, perform initialization of the number of starter operations stored in the engine stop and start ECU Click here.

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

Tech Tips

Using the GTS, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting.

PROCEDURE


  1. CHECK CRANKING OPERATION


    1. Operate the ignition or starter switch, or push start switch to crank the engine.

      Result
      Result Proceed to
      The engine cranks A
      The engine does not crank B

    B

    PERFORM ACTIVE TEST USING GTS (Starter) Click here

    A

  2. PERFORM ACTIVE TEST USING GTS (Starter)


    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 / Stop and Start / Active Test / Starter.

    5. When the starter is activated by Active Test, check whether the engine cranks.

      Note

      Starter operation in the Active Test stops automatically in 3 seconds.

      OK
      The engine cranks.

    OK

    GO TO DTC P1603 CHART Click here

    NG

  3. INSPECT ENGINE STOP AND START ECU


    1. Disconnect the A72 and F90 engine stop and start ECU connectors.

    2. A005KFOE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Stop and Start ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A72-7 (BIN) - Body ground Always 9.5 to 14 V

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A72-5 (+B) - Body ground Ignition switch ON 9.5 to 14 V
      F90-17 (IG1) - Body ground Ignition switch ON 9.5 to 14 V
      F90-20 (IG2) - Body ground Ignition switch ON 9.5 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BODY GROUND)


    1. Disconnect the A72 and A73 engine stop and start ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A72-8 (GND) - Body ground Always Below 1 Ω
      A73-17 (VB-) - Body ground Always Below 1 Ω

    OK

    REPLACE ENGINE STOP AND START ECU Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

  5. PERFORM ACTIVE TEST USING GTS (Starter)


    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 / Stop and Start / Active Test / Starter.

    5. When the starter is activated by Active Test, check whether the engine cranks.

      Note

      Starter operation in the Active Test stops automatically in 3 seconds.

      OK
      The engine cranks

    NG

    INSPECT ENGINE STOP AND START ECU Click here

    OK

  6. READ VALUE USING GTS (NEUTRAL SWITCH)


    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 / Stop and Start / Data List / Neutral Switch.

    5. Read the Data Monitor when the shift lever is operated.

      Stop and Start
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Neutral Switch

      Displays the shift position N or P /

      Displays ON or OFF

      ON: Shift lever is in N or P

      OFF: Shift lever is in other than N or P

      		 -
      Result
      Result Proceed to
      Data Monitor display is not within standards A

      Data Monitor display is within standards

      ( w/o Entry and Start System)

      		 B

      Data Monitor display is within standards

      ( w/ Entry and Start System)

      		 C

    B

    INSPECT IGNITION OR START SWITCH ASSEMBLY Click here

    C

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE STOP AND START ECU) Click here

    A

  7. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly Click here.

      Result
      Result Proceed to

      OK

      (w/o Entry and Start System)

      		 A

      OK

      ( w/ Entry and Start System)

      		 B
      NG C

    B

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE STOP AND START ECU) Click here

    C

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    A

  8. CHECK HARNESS AND CONNECTOR (IGNITION OR START SWITCH ASSEMBLY - ST/MGC RELAY)


    1. Disconnect the F13 ignition or start switch assembly connector.

    2. Remove the ST/MGC relay from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F13-7 (ST2) - ST/MGC relay holder 2 Shift lever is in N or P Below 1 Ω
      F13-7 (ST2) - ST/MGC relay holder 2 Shift lever is in other than N or P 10 kΩ or more

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

  9. INSPECT IGNITION OR START SWITCH ASSEMBLY


    1. Inspect the ignition or start switch assembly Click here.


    NG

    REPLACE IGNITION OR START SWITCH ASSEMBLY

    OK

  10. CHECK HARNESS AND CONNECTOR (IGNITION OR START SWITCH ASSEMBLY - BATTERY)


    1. Disconnect the F13 ignition or start switch assembly connector.

    2. A005H5ZE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Ignition Switch or Start Switch Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F13-5 (AM2) - Body ground Always 9.5 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  11. CHECK HARNESS AND CONNECTOR (IGNITION OR START SWITCH ASSEMBLY - PARK/NEUTRAL POSITION SWITCH)


    1. Disconnect the F13 ignition or start switch assembly connector.

    2. Disconnect the B90 park/neutral position switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F13-7 (ST2) - B90-4 (B) Always Below 1 Ω
      F13-7 (ST2) or B90-4 (B) - Body ground Always 10 kΩ or more

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

  12. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE STOP AND START ECU)


    1. Disconnect the B90 park/neutral position switch connector.

    2. Disconnect the F65 certification ECU (smart key ECU assembly) connector.

    3. Disconnect the A73 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
      F65-5 (STAR) - A73-28 (CLL) Always Below 1 Ω
      F65-5 (STAR) or A73-28 (CLL) - Body ground Always 10 kΩ or more

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  13. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BATTERY)


    1. Disconnect the A73 engine stop and start ECU connector.

    2. A005I5OE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Stop and Start ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A73-28 (CLL) - Body ground Engine start operation (when the push start switch is pushed) due to the use of the push start switch 9.5 to 14 V

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    GO TO ENTRY AND START SYSTEM Click here

  14. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE STOP AND START ECU)


    1. Remove the ST/MGC relay from the No. 2 engine room relay block.

    2. Disconnect the F65 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F65-5 (STAR) - ST/MGC relay holder 2 Shift lever is in N or P Below 1 Ω
      F65-5 (STAR) - ST/MGC relay holder 2 Shift lever is in other than N or P 10 kΩ or more

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

  15. INSPECT ENGINE STOP AND START ECU


    1. Connect an oscilloscope to the STA, STA2 and GND terminals of the engine stop and start ECU connector.

      A005ITIE02
      Text in Illustration
      *a

      Component with harness connected

      (Engine Stop and Start ECU)

      		 - -
    2. A005GLAE24
      *1 0.03 to 0.06 seconds

      Check the waveform immediately after starting

      Item Condition
      Tester connection

      CH1: A73-21 (STA) - A72-8 (GND)

      CH2: A73-23 (STA2) - A72-8 (GND)
      Condition Engine starting by operating the ignition or starter switch assembly, or pushing the push start switch
      Result
      Tester Connection Condition Specified Condition Proceed to

      A73-21 (STA) - A72-8 (GND)

      A73-23 (STA2) - A72-8 (GND)

      		 Engine starting by operating the ignition or starter switch assembly, or pushing the push start switch Time from ST/MGC relay on to ST2 relay on is within a 0.03 to 0.06 second frame A
      Time from ST/MGC relay on to ST2 relay on is not within a 0.03 to 0.06 second frame B
      ST/MGC relay turns on but ST2 relay remains off C
      Both ST/MGC relay and ST2 relay remain off D

      Note

      After replacing the engine stop and start ECU, check that there is no malfunction in the ring gear or starter pinion. Malfunctions in the delay circuit may cause wear in the ring gear or starter pinion.


    B

    REPLACE ENGINE STOP AND START ECU Click here

    C

    INSPECT ENGINE STOP AND START ECU Click here

    D

    CHECK HARNESS AND CONNECTOR (ST/MGC RELAY - BODY GROUND) Click here

    A

  16. INSPECT RELAY (ST/MGC, ST2 RELAY)


    1. Inspect the ST/MGC relay Click here.

    2. Inspect the ST2 relay Click here.


    NG

    REPLACE RELAY (ST/MGC, ST2 RELAY)

    OK

  17. CHECK HARNESS AND CONNECTOR (ST/MGC, ST2 RELAY - BATTERY)


    1. Remove the ST/MGC relay from the No. 2 engine room relay block.

    2. Remove the ST2 relay from the engine room relay block.

      A005LROE01
      Text in Illustration
      *1 Engine Room Relay Block *2 No. 2 Engine Room Relay Block
      *a ST2 Relay Holder *b ST/MGC Relay Holder

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      ST/MGC relay holder 5 - body ground Always 9.5 to 14 V
      ST2 relay holder 5 - body ground Always 9.5 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  18. CHECK HARNESS AND CONNECTOR (ST/MGC, ST2 RELAY - STARTER)


    1. Remove the ST/MGC relay from the No. 2 engine room relay block.

    2. Remove the ST2 relay from the engine room relay block.

    3. Disconnect the B87 starter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST/MGC relay holder 3 - B87-2 Always Below 1 Ω
      ST2 relay holder 3 - B87-1 Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  19. CHECK HARNESS AND CONNECTOR (ST/MGC RELAY - BODY GROUND)


    1. Remove the ST/MGC relay from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST/MGC relay holder 1 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  20. CHECK HARNESS AND CONNECTOR (ST2 RELAY - BODY GROUND)


    1. Remove the ST2 relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST2 relay holder 1 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  21. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ST/MGC RELAY)


    1. Disconnect the F65 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the B90 park/neutral position switch connector.

    3. Disconnect the A73 engine stop and start ECU connector.

    4. Remove the ST/MGC relay from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A73-21 (STA) - ST/MGC relay holder 2 Always Below 1 Ω
      A73-21 (STA) - Body ground Always 10 kΩ or higher
      ST/MGC relay holder 2 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  22. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ST2 RELAY)


    1. Disconnect the A58 ECM connector.

    2. Disconnect the A73 engine stop and start ECU connector.

    3. Remove the ST2 relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A73-23 (STA2) - ST2 relay holder 2 Always Below 1 Ω
      A73-23 (STA2) - Body ground Always 10 kΩ or higher
      ST2 relay holder 2 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  23. CHECK STARTER OPERATION


    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 / Stop and Start / Active Test / Starter Motor Drive Magnet Switch.

    5. Connect the oscilloscope positive probe to the positive (+) terminal on the battery, and the negative probe to the negative (-) terminal on the battery.

    6. Read the number of drops in the waveform when the Starter Motor of the Active Test is performed.

      Note


      • Starter motor operation during the Active Test stops automatically in 3 seconds.

      • Do not force the starter pinion to operate.

      A005KK4E04
      OK
      There are 2 drops from approximately 12 V in waveform.
      Result
      Number of drops in waveform Proceed to
      No change from approximately 12 V A
      2 drops from approximately 12 V in waveform B

    B

    INSPECT STARTER ASSEMBLY Click here

    A

  24. INSPECT STARTER INRUSH CURRENT REDUCTION RELAY


    1. Disconnect cable from the negative battery terminal.

    2. Disconnect the B and M starter inrush current reduction relay terminal.

    3. A005LECE02
      Text in Illustration
      *1 Starter Assembly
      *a B terminal
      *b M terminal

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      B terminal - M terminal Always Below 1 Ω

    NG

    INSPECT STARTER ASSEMBLY (M TERMINAL) Click here

    OK

  25. INSPECT STARTER ASSEMBLY (C TERMINAL)


    1. Disconnect cable from the negative battery terminal.

    2. Disconnect the B starter inrush current reduction relay terminal.

    3. Disconnect the C starter assembly terminal.

    4. A005LBPE02
      Text in Illustration
      *1 Starter Assembly
      *a Check Part
      *b C terminal
      *c B terminal

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C terminal - M terminal Always Below 1 Ω

    OK

    REPLACE STARTER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

  26. INSPECT STARTER ASSEMBLY (M TERMINAL)


    1. Disconnect cable from negative battery terminal.

    2. Disconnect M starter inrush current reduction relay terminal.

    3. A005HZTE02
      Text in Illustration
      *1 Starter Assembly
      *a Check Part
      *b M terminal

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      M terminal - Body ground Always Below 1 Ω

    OK

    REPLACE STARTER INRUSH CURRENT REDUCTION RELAY

    NG

    REPLACE STARTER ASSEMBLY Click here

  27. INSPECT STARTER ASSEMBLY


    1. Inspect the starter assembly Click here.


    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE STARTER ASSEMBLY Click here

  28. INSPECT ENGINE STOP AND START ECU


    1. Disconnect the A72 and F90 engine stop and start ECU connectors.

    2. A005IL4E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Engine Stop and Start ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A72-7 (BIN) - Body ground Always 9.5 to 14 V

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A72-5 (+B) - Body ground Ignition switch ON 9.5 to 14 V
      F90-17 (IG1) - Body ground Ignition switch ON 9.5 to 14 V
      F90-20 (IG2) - Body ground Ignition switch ON 9.5 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  29. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BODY GROUND)


    1. Disconnect the A72 and A73 engine stop and start ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A72-8 (GND) - Body ground Always Below 1 Ω
      A73-17 (VB-) - Body ground Always Below 1 Ω

    OK

    REPLACE ENGINE STOP AND START ECU Click here

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR