LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2014 >> Corolla LE Eco Plus >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 16 (Engine Control System (2ZR-FE) - Diagnostic Codes (2 Of 7) (Model Code: ZRE172)) >> SFI System >> DTC P0504: Brake Switch "A" / "B" Correlation [08/2016 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0504: Brake Switch "A" / "B" Correlation [08/2016 - ]: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the stop light switch assembly connector.
      GTY430273Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Stop Light Switch Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A1-2 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - BATTERY) 

    Result:  1

    OK 

    See step  2

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the stop light switch assembly connector.
      GTY430273Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Stop Light Switch Assembly)
    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
      A1-4 - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - IG2 RELAY) 

    Result:  1

    OK 

    See step  3

  3. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Inspect the stop light switch assembly.

      Refer to INSPECTION [08/2013 - ]

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [08/2013 - ] 

    Result:  1

    OK 

    See step  4

  4. CHECK TERMINAL VOLTAGE (STP AND ST1- VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY446204Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Brake Pedal Depressed *b Brake Pedal Released
      *c Front view of wire harness connector
      (to ECM)      		 - -
    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
      A40-10 (ST1-) - Body ground Brake pedal released 7.5 to 14 V
      Brake pedal depressed Below 1.5 V
      A40-9 (STP) - Body ground Brake pedal released Below 1.5 V
      Brake pedal depressed 7.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    REPLACE ECM. Refer to  REMOVAL [08/2016 - ] 

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM) 

scientia non olet · About LEMON Manuals