VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1249/49

DTC Code DTC Name
C1249/49 Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU inputs the stop light switch signal and the condition of brake operation.

The skid control ECU has an open detection circuit, which outputs this DTC when an open circuit is detected in the stop light switch input circuit while the stop light switch is OFF.

DTC Code DTC Detection Condition Trouble Area
C1249/49

Either of the following is detected:


  1. When IG1 terminal voltage is 9.5 to 18.5 V, an open stop light switch circuit continues for 0.3 seconds or more.

  2. When the brake pedal load sensing switch is ON, the master cylinder pressure is 2 MPa or more and the deceleration calculated from the vehicle speed is 0.2 G or more, the stop light switch is OFF for 2 seconds or more.

  • STOP SW fuse

  • Stop light switch

  • Stop light switch circuit

  • Stop light control (BRK-LP) relay

  • Stop light control (BRK-LP) relay circuit

  • Skid control ECU

WIRING DIAGRAM

A0161CEE01
A01618PE01

INSPECTION PROCEDURE

Note

When replacing the skid control ECU, perform zero point calibration and store system information Click here.

PROCEDURE


  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

    INSPECT STOP SW FUSE Click here

    OK

  2. READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH AND BRAKE PEDAL LOAD SENSING SWITCH)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Select the Data List mode on the intelligent tester Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item / Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch / ON or OFF

      ON: Brake pedal depressed

      OFF: Brake pedal released

      		 -
      Brake Pedal Load Sensing SW Brake pedal load sensing switch / ON or OFF

      ON: Brake pedal depressed beyond the specified point

      OFF: Brake pedal not depressed beyond the specified point

      		 -

    4. Check that the stop light display observed on the intelligent tester changes when the brake pedal is depressed.

      OK
      When the brake pedal is depressed, the intelligent tester displays "ON".

    5. Depress the brake pedal slowly, and check when the stop light switch and brake pedal load sensing switch turn ON.

      OK
      First the stop light switch should turn ON, and then the brake pedal load sensing switch should turn ON.
      Result
      Result Proceed to
      OK A
      NG (The stop light switch does not turn on) B
      NG (The brake pedal load sensing switch turns on first) C

    B

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK) Click here

    C

    CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION Click here

    A

  3. INSPECT SKID CONTROL ECU (IG1 TERMINAL)


    1. A0163E5E06

      Turn the engine switch off.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    3. Disconnect the skid control ECU connector.

    4. Turn the engine switch on (IG).

    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      J77-1 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    OK

  4. INSPECT SKID CONTROL ECU (GND TERMINAL)


    1. A015ZCGE04

      Turn the engine switch off.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    3. Disconnect the skid control ECU connectors.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      J78-26 (GND1) - Body ground Always Below 1 Ω
      J78-14 (GND2) - Body ground Always Below 1 Ω
      A35*1, J98*2-22 (GND3) - Body ground Always Below 1 Ω

      *1: for LHD

      *2: for RHD


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

    OK

  5. RECONFIRM DTC


    1. Reconnect the skid control ECU connectors.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Depress the brake pedal several times to test the stop light circuit.

    5. Check if the same DTC is recorded Click here.

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

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    B

    REPLACE SKID CONTROL ECU Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

  6. INSPECT STOP SW FUSE


    1. A0163J7E02

      Remove the STOP SW fuse from the main body ECU RH (cowl side junction block RH).

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      STOP SW (7.5 A) fuse Always Below 1 Ω

    NG

    REPLACE STOP SW FUSE

    OK

  7. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)


    1. A015ZQ9E05

      Install the STOP SW fuse.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    3. Disconnect the stop light switch connector.

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A22-2 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  8. INSPECT STOP LIGHT SWITCH


    1. A0163A4E01

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher

    NG

    REPLACE STOP LIGHT SWITCH Click here

    OK

  9. INSPECT STOP LIGHT CONTROL RELAY (BRK-LP)


    1. A0162XNE11

      Remove the stop light control (BRK-LP) relay.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 4 Voltage is not applied between terminals 1 and 2 Below 1 Ω

    NG

    REPLACE STOP LIGHT CONTROL RELAY (BRK-LP)

    OK

  10. INSPECT STOP LIGHT CONTROL RELAY


    1. Check the stop light control relay Click here.

      OK
      The stop light control relay is normal.

    NG

    REPLACE STOP LIGHT CONTROL RELAY Click here

    OK

  11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - STOP LIGHT CONTROL RELAY)


    1. A015Z05E02

      Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the stop light control relay connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A22-1 - J99-2 (STP) Always Below 1 Ω
      A22-1 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  12. CHECK HARNESS AND CONNECTOR (STOP LIGHT CONTROL RELAY - ENGINE ROOM NO. 3 RELAY BLOCK)


    1. A01630EE02

      Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      J99-8 (OUT) - Stop light control (BRK-LP) relay terminal 4 Always Below 1 Ω
      J99-8 (OUT) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)


    1. A015ZCSE03

      Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the skid control ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      J77-10 (STP1) - Stop light control (BRK-LP) relay terminal 3 Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Start the engine.

    3. Depress the brake pedal several times to test the stop light circuit.

    4. Check if the same DTC is recorded Click here.

      Tech Tips

      Reinstall the relay, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

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

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    B

    REPLACE SKID CONTROL ECU Click here

    A

    INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Click here

  15. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)


    1. A015ZCSE03

      Turn the engine switch off.

    2. Remove the stop light control (BRK-LP) relay.

    3. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    4. Disconnect the skid control ECU connector.

    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      J77-10 (STP1) - Stop light control (BRK-LP) relay terminal 3 Always Below 1 Ω

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE SKID CONTROL ECU Click here

  16. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION


    1. Turn the engine switch off.

    2. Check the brake pedal height and stop light switch installation Click here.

      OK
      The brake pedal height and stop light switch installation are normal.

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    NG

    ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH Click here

    OK

    REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH) Click here