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DTC C1249/49: Open in Stop Light Switch Circuit [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK STOP LIGHT OPERATION 
    1. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

      OK

      Condition Illumination Condition
      Brake pedal depressed. ON
      Brake pedal released. OFF

    NG → See step   4 

    OK: Go to next step 

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH ASSEMBLY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Select the Data List on the Techstream. Refer to DATA LIST / ACTIVE TEST [08/2013 - ] .
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch assembly / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
      -
    4. Check that the stop light switch assembly display observed on the Techstream changes according to brake pedal operation.

      OK

      The Techstream displays ON or OFF according to brake pedal operation.

    NG → See step   9 

    OK: Go to next step 

  3. RECONFIRM DTC 
    1. Turn the power switch off.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
    3. Turn the power switch on (READY).
    4. Depress the brake pedal several times to test the stop light circuit.
    5. Check if the same DTC is output. Refer to DTC CHECK / CLEAR [08/2013 - ] .

      Result

      Result Proceed to
      DTC C1249/49 is not output. A
      DTC C1249/49 is output. B

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

    B → See step   10 

    A → See step   12 

  4. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Check the stop light switch assembly. Refer to ON-VEHICLE INSPECTION [08/2013 - ] .

      OK

      The stop light switch assembly is normal.

    NG → See step   13 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (STPS TERMINAL) 
    1. Disconnect the 1F No. 1 integration relay (engine room junction block assembly) connector.
      GTY404570Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      1F-16 (STPS) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      1F-16 (STPS) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 1 Integration Relay (Engine Room Junction Block Assembly))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (STPS CIRCUIT) 

    OK: Go to next step 

  6. INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY 
    1. Reconnect the 1F No. 1 integration relay (engine room junction block assembly) connector.
    2. Check the No. 1 integration relay (engine room junction block assembly). Refer to ON-VEHICLE INSPECTION [08/2013 - ] .

      OK

      The No. 1 integration relay (engine room junction block assembly) is normal.

    NG → See step   14 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
      GTY408391Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A24-6 (STP2) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      A24-6 (STP2) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      A24-33 (STP) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      A24-33 (STP) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

    OK: Go to next step 

  8. RECONFIRM DTC 
    1. Reconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
    3. Turn the power switch on (READY).
    4. Depress the brake pedal several times to test the stop light circuit.
    5. Check if the same DTC is output. Refer to DTC CHECK / CLEAR [08/2013 - ] .

      Result

      Result Proceed to
      DTC C1249/49 is not output. A
      DTC C1249/49 is output. B

      HINT: 

      • If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .
      • If the lighting system is normal but the DTC is still output, replace the skid control ECU (brake booster with master cylinder assembly). Refer to REMOVAL [08/2013 - ] .

    B → See step   11 

    A → See step   12 

  9. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Turn the power switch off.
      GTY414846Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the A24 skid control ECU (brake booster with master cylinder assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A24-33 (STP) - Body ground Stop light switch assembly ON (Brake pedal depressed) 11 to 14 V
      A24-33 (STP) - Body ground Stop light switch assembly OFF (Brake pedal released) Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step. Refer to PROBLEM SYMPTOMS TABLE [08/2013 - ] .

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

    OK → See step   10 

  10. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [08/2013 - ] 
  11. INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ] 
  12. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ] 
  13. REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [08/2013 - ] 
  14. REPAIR OR REPLACE WIRE HARNESS OR ENGINE ROOM JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [08/2013 - ]