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Home >> Lexus >> 2025 >> NX 350h >> Repair and Diagnosis >> External Pages >> Different car >> Section 64 (Stop And Start System - Diagnostic Codes (1 Of 2)) >> Stop And Start System >> DTC P2530-14: Ignition Switch Circuit Short to Ground or Open [11/2021 - 03/2023] >> Procedure

DTC P2530-14: Ignition Switch Circuit Short to Ground or Open [11/2021 - 03/2023]: Procedure

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  1. READ VALUE USING GTS (IG SWITCH) 
    1. According to the display on the GTS, read the Data List.

      Powertrain > Stop and Start > Data List 

      Tester Display
      IG Switch

      Result

      Tester Display Result Proceed to
      IG Switch ON A
      OFF B

    Result: 

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

    Result: 

    See step  2

  2. CHECK ENGINE STOP AND START ECU (IGP TERMINAL VOLTAGE) 
    GTY1065968Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Engine Stop and Start ECU)
    - -
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      D40-18 (IGP) - Body ground Ignition switch ON 9.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. CHECK ENGINE STOP AND START ECU (+B TERMINAL VOLTAGE) 
    GTY1065977Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Engine Stop and Start ECU)
    - -
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A29-1 (+B) - Body ground Ignition switch ON 9.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

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

    Result: 

    NG 

    See step  4

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A29-1 (+B) - 5 (EFI-MAIN NO. 1 relay holder) Always Below 1 Ω
      A29-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      5 (EFI-MAIN NO. 1 relay holder) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO ECM POWER SOURCE CIRCUIT 

    for A25A-FKS: Refer to ECM Power Source Circuit [11/2021 - ]

    for T24A-FTS: Refer to ECM Power Source Circuit [11/2021 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      D40-18 (IGP) - 3 (IGP NO. 1 relay holder) Always Below 1 Ω
      D40-18 (IGP) - Body ground and other terminals Always 10 kΩ or higher
      3 (IGP NO. 1 relay holder) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SMART ACCESS SYSTEM. Refer to  Power Source Mode does not Change to ON (IG) [11/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR