Dtc P0724 Brake Switch B Circuit High

Engine Hybrid System. Yaris. Ncp93, 131
1Nz-Fe Engine Control. Yaris. Ncp93, 131

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

CHECK STOP LIGHT SWITCH ASSEMBLY INSTALLATION

INSPECT STOP LIGHT SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM)

DTC P0724 Brake Switch "B" Circuit High


DESCRIPTION

The stop light switch is part of a duplex system that transmits 2 signals: STP and ST1-. These 2 signals are used by the ECM to monitor whether or not the brake system is working properly. This DTC indicates that the stop light switch remains on. When the stop light switch remains on during GO and STOP driving, the ECM interprets this as a fault in the stop light switch. Then the MIL illuminates and the ECM stores the DTC.

DTC No.
DTC Detection Condition
Trouble Area
P0724
The stop light switch remains on even when the vehicle repeats 5 cycles of STOP (less than 3 km/h [1.86 mph]) and GO (30 km/h [18.65 mph] or more) (2 trip detection logic).
  1. Short in stop light switch signal circuit
  2. Stop light switch assembly
  3. ECM

MONITOR DESCRIPTION

This DTC indicates that the stop light switch remains on. When the stop light switch remains on during "STOP and GO" driving, the ECM interprets this as a fault in the stop light switch. The ECM turns on MIL and stores the DTC. The vehicle must STOP (less than 3 km/h [1.86 mph]) and GO (30 km/h [18.65 mph] or more) 5 times during 2 driving cycles, in order to detect a malfunction.

MONITOR STRATEGY


Related DTCs
P0724: Stop Light Switch/Range Check/Rationality
Required Sensors/Components (Main)
Stop light switch assembly
Required Sensors/Components (Related)
Speed sensor
Frequency of Operation
Continuous
Duration
GO and STOP 5 times
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


Monitor runs whenever following DTCs not present
None
Battery voltage
8 V or higher
Starter
OFF
Ignition Switch
ON
GO: 30 km/h (18.65 mph) or more
Once
STOP: Less than 3 km/h (1.86 mph)
Once

TYPICAL MALFUNCTION THRESHOLDS


Stop light switch status
Stuck on

CONFIRMATION DRIVING PATTERN


Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P0724 Brake Switch B Circuit High

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on [A].
  6. Wait 5 seconds after clearing DTCs.
  7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [B].
  8. Read pending DTCs.
    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  9. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  10. Input the DTC: P0724.
  11. Check the DTC judgment result.

    Techstream Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    N/A
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, perform steps [C] through [E].
  12. Start the engine [C].
  13. Accelerate the vehicle to 30 km/h (18.65 mph) or more, depress the brake pedal and decelerate the vehicle to 3 km/h (1.86 mph) or less [D]. Repeat step [D] 5 times.
    CAUTION:
    When performing the confirmation driving pattern, obey all speed limits and traffic laws.
  14. Check the DTC judgment result [E].
  15. If no pending DTC is output, perform a universal trip and check for permanent DTCs (YARIS_NCP93 RM000000PDK0T5X.html).
    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0504 (YARIS_NCP93 RM000000XCT0MNX_02.html).

INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
  1. Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
  2. Using the Techstream, the Data List item "Stop Light Switch" and "ST1" can be read (YARIS_NCP93 RM000000XCT0MNX_03.html).
1.READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Powertrain / Engine and ECT / Data List / Stop Light Switch.

  1. Read the values displayed on the Techstream.


OK:

Techstream Display
Measurement Item/Range (display)
Normal Condition
Stop Light Switch
Stop light switch status:
ON or OFF
  1. ON: Brake pedal depressed
  2. OFF: Brake pedal released


NG
Go to step 2
OK

CHECK FOR INTERMITTENT PROBLEMS (YARIS_NCP93 RM000000PDQ0Q2X.html)

2.CHECK STOP LIGHT SWITCH ASSEMBLY INSTALLATION

  1. Check the stop light switch assembly installation (YARIS_NCP93 RM000000ORB01UX_01_0001.html).

    OK:
    Stop light switch assembly is installed correctly.


NG
SECURELY REINSTALL STOP LIGHT SWITCH ASSEMBLY (YARIS_NCP93 RM000004O2F008X.html)
OK


3.INSPECT STOP LIGHT SWITCH ASSEMBLY

  1. Inspect the stop light switch assembly (YARIS_NCP93 RM000001Y5401QX.html).



NG
REPLACE STOP LIGHT SWITCH ASSEMBLY (YARIS_NCP93 RM000004O2H008X.html)
OK


4.CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - ECM)

  1. Disconnect the ECM connector.



    Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan). Dtc P0724 Brake Switch B Circuit High

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A72-9 (STP) - Body ground
    		Brake pedal released
    		0 to 1.5 V
    Brake pedal depressed
    		7.5 to 14 V
    Text in Illustration
    *a
    		Brake pedal depressed
    *b
    		Brake pedal released
    *c
    		Front view of wire harness connector
    (to ECM)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (YARIS_NCP93 RM000001CN002IX.html)