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DTC P0615-62: Starter Relay Signal Compare Failure [11/2021 - 03/2023]: Procedure

  1. READ VALUE USING GTS (ENGINE STARTER SIGNAL) 
    1. Read the values displayed on the GTS when the ignition switch is ON and START.

      Powertrain > Stop and Start > Data List 

      Tester Display
      Engine Starter Signal

      OK

      Tester Display Condition Normal Condition
      Engine Starter Signal Ignition switch ON OFF
      Ignition switch START ON

      Result

      Result Proceed to
      OK A
      NG
      (for A25A-FKS)      		 B
      NG
      (for T24A-FTS)      		 C

    Result: 

    B 

    See step  5

    Result: 

    C 

    See step  8

    Result: 

    A 

    See step  2

  2. READ VALUE USING GTS (STARTER SW) 
    1. Enter the following menus: Powertrain / Engine / Data List / Starter SW.
    2. Read the values displayed on the GTS when the ignition switch is ON and START.

      Powertrain > Engine > Data List 

      Tester Display
      Starter SW

      OK

      Tester Display Condition Normal Condition
      Starter SW Ignition switch ON OFF
      Ignition switch START ON

      Result

      Result Proceed to
      OK A
      NG
      (for A25A-FKS)      		 B
      NG
      (for T24A-FTS)      		 C

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ] 

    Result: 

    C 

    See step  4

    Result: 

    B 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (ECM - ST NO. 1 RELAY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the ECM connector.
    3. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    4. Disconnect the certification ECU (smart key ECU assembly) connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A20-30 (STA) - ST NO. 1 relay terminal 2 Always Below 1 Ω
      A20-30 (STA) - Body ground Always 10 kΩ or higher
      ST NO. 1 relay terminal 2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  4. CHECK HARNESS AND CONNECTOR (ECM - ST NO. 1 RELAY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the ECM connector.
    3. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    4. Disconnect the certification ECU (smart key ECU assembly) connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A19-16 (STA) - ST NO. 1 relay terminal 2 Always Below 1 Ω
      A19-16 (STA) - Body ground Always 10 kΩ or higher
      ST NO. 1 relay terminal 2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ECM - ST NO. 1 RELAY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the ECM connector.
    3. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    4. Disconnect the certification ECU (smart key ECU assembly) connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A20-30 (STA) - ST NO. 1 relay terminal 2 Always Below 1 Ω
      A29-21 (STA) - A20-30 (STA) Always Below 1 Ω
      A20-30 (STA) - Body ground Always 10 kΩ or higher
      A29-21 (STA) - Body ground Always 10 kΩ or higher
      ST NO. 1 relay terminal 2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT RELAY (ST NO. 1 RELAY) 
    1. Inspect the ST NO. 1 relay.

      Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (ST NO. 1 RELAY) 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - BODY GROUND) 
    1. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      ST NO. 1 relay terminal 1 - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - ECM - ST NO. 1 RELAY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the ECM connector.
    3. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    4. Disconnect the certification ECU (smart key ECU assembly) connector.
    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A19-16 (STA) - ST NO. 1 relay terminal 2 Always Below 1 Ω
      A29-21 (STA) - A19-16 (STA) Always Below 1 Ω
      A19-16 (STA) - Body ground Always 10 kΩ or higher
      A29-21 (STA) - Body ground Always 10 kΩ or higher
      ST NO. 1 relay terminal 2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. INSPECT RELAY (ST NO. 1 RELAY) 
    1. Inspect the ST NO. 1 relay.

      Refer to ON-VEHICLE INSPECTION [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RELAY (ST NO. 1 RELAY) 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - BODY GROUND) 
    1. Remove the ST NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      ST NO. 1 relay terminal 1 - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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