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Home >> Toyota >> 2024 >> Corolla LE >> Repair and Diagnosis >> External Pages >> Different car >> Section 257 (Engine Control System (2ZR-FAE) - Diagnostic Codes (4 Of 8)) >> SFI System >> DTC P0504: Brake Switch "A" / "B" Correlation [01/2019 - 03/2019] >> Procedure

DTC P0504: Brake Switch "A" / "B" Correlation [01/2019 - 03/2019]: Procedure

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  1. CHECK TERMINAL VOLTAGE (STOP LIGHT SWITCH ASSEMBLY) 
    GTY865034Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Stop Light Switch Assembly)
    1. Disconnect the stop light switch assembly connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A53-7 (B) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  2

  2. CHECK TERMINAL VOLTAGE (STOP LIGHT SWITCH ASSEMBLY) 
    GTY865030Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Stop Light Switch Assembly)
    1. Disconnect the stop light switch assembly connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A53-6 (B) - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  6

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - BODY GROUND) 
    1. Disconnect the stop light switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A53-2 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK TERMINAL VOLTAGE (ECM) 
    GTY873457Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Brake Pedal Depressed *b Brake Pedal Released
    *c Front view of wire harness connector
    (to ECM)
    - -
    1. Disconnect the ECM connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Brake Pedal Operation Specified Condition
      A46-10 (ST1-) - Body ground Released 7.5 to 14 V
      Depressed Below 1.5 V
      A46-9 (STP) - Body ground Released Below 1.5 V
      Depressed 7.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM 

    Refer to REMOVAL [01/2019 - 03/2019]

    Result: 

    NG 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM) 
    1. Disconnect the stop light switch assembly connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A53-5 (L) - A46-10 (ST1-) Always Below 1 Ω
      A53-3 (L) - A46-9 (STP) Always Below 1 Ω
      A53-5 (L) or A46-10 (ST1-) - Body ground and other terminals Always 10 kΩ or higher
      A53-3 (L) or A46-9 (STP) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STOP LIGHT SWITCH ASSEMBLY 

    Refer to REMOVAL [06/2018 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the instrument panel junction block assembly connector.
    2. Disconnect the stop light switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4B-15 - A53-6 (B) Always Below 1 Ω
      4B-15 or A53-6 (B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BODY GROUND) 
    1. Disconnect the instrument panel junction block assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4F-3 - Body ground Always Below 1 Ω

      Result

      Result  Proceed to
      OK (w/ Smart Key System) A
      OK (w/o Smart Key System) B
      NG C

    Result: 

    See step  10

    Result: 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the instrument panel junction block assembly connector.
    2. Disconnect the 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
      4E-17 - I1-15 (IG1D) Always Below 1 Ω
      4E-17 or I1-15 (IG1D) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK SMART KEY SYSTEM 
    1. Check the smart key system.

      Refer to HOW TO PROCEED WITH TROUBLESHOOTING [01/2019 - 09/2022]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    Refer to REMOVAL [01/2019 - 03/2019]

    Result: 

    NG 

    REPAIR SMART KEY SYSTEM 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [01/2019 - 09/2022]

  10. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - IGNITION OR STARTER SWITCH ASSEMBLY) 
    1. Disconnect the instrument panel junction block assembly connector.
    2. Disconnect the ignition or starter switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4E-17 - I12-8 (IG1) Always Below 1 Ω
      4E-17 or I12-8 (IG1) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  11

  11. CHECK ECM POWER SOURCE CIRCUIT 
    1. Check the ECM power source circuit.

      Refer to ECM Power Source Circuit [01/2019 - 09/2022]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    Refer to REMOVAL [01/2019 - 03/2019]

    Result: 

    NG 

    REPAIR ECM POWER SOURCE CIRCUIT 

    Refer to ECM Power Source Circuit [01/2019 - 09/2022]

  12. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the instrument panel junction block assembly connector.
    2. Disconnect the stop light switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4B-3 - A53-7 (B) Always Below 1 Ω
      4B-3 or A53-7 (B) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

  13. CHECK TERMINAL VOLTAGE (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    GTY926490Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Instrument Panel Junction Block Assembly)
    1. Disconnect the instrument panel junction block assembly connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      4C-1 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 

    Refer to REMOVAL [01/2019 - 03/2019]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)