DTC    P0724    Brake Switch "B" Circuit High

for Preparation Click here


DESCRIPTION

The purpose of this circuit is to prevent the engine from stalling while driving in the lock-up condition when the brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signal to the ECM. Then the ECM cancels the operation of the lock-up clutch while braking is in progress.

DTC No.
DTC Detection Condition
Trouble Area
P0724
Stop light switch remains ON even when vehicle is driven in GO (30 km/h (19 mph) or more) and STOP (less than 3 km/h (2 mph)) pattern 5 times
(2 trip detection logic)
  1. Short in stop light switch signal circuit
  2. Stop light switch
  3. ECM

WIRING DIAGRAM

Refer to DTC P0504 (Click here).

INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:
  1. The following procedure is based on the premise that the stop lights are functioning normally. If the stop lights are not functioning, proceed to Stop Light Circuit (Click here).
  2. Read freeze frame data using the intelligent tester. 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.

1.READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

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

  1. Read the value displayed on the tester with the brake pedal depressed and released.

    OK:
    Brake Pedal
    		Display
    Released
    		OFF
    Depressed
    		ON



NG
Go to step 2
OK

CHECK FOR INTERMITTENT PROBLEMS (Click here)  

2.INSPECT STOP LIGHT SWITCH ASSEMBLY


    A115657E12

  1. Remove the stop light switch.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    1 - 2
    		Switch pin not pushed
    		Below 1 Ω
    Switch pin pushed
    		10 kΩ or higher
    3 - 4
    		Switch pin not pushed
    		10 kΩ or higher
    Switch pin pushed
    		Below 1 Ω

  1. Reinstall the stop light switch.



NG
REPLACE STOP LIGHT SWITCH ASSEMBLY (Click here)
OK


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

  1. Disconnect the stop light switch connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    A18-36 (STP) - A27-1
    		Always
    		Below 1 Ω
    A18-35 (ST1-) - A27-4
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    A18-36 (STP) or A27-1 - Body ground
    		Always
    		10 kΩ or higher
    A18-35 (ST1-) or A27-4 - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the ECM connector.

  1. Reconnect the stop light switch connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (Click here)