DTC P0703-12: Brake Switch "B" Circuit Short to Battery [10/2017 - ]: Description

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The purpose of this circuit is to prevent the engine from stalling when the brakes are suddenly applied while driving in the lock-up condition.

When the brake pedal is depressed, the stop light switch assembly sends a signal to the ECM. The ECM then cancels the operation of the lock-up clutch while braking is in progress.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P0703-12	Brake Switch "B" Circuit Short to Battery	All of the following conditions are met (2-trip detection logic): The engine switch is on (IG). The battery voltage is 8 V or more. The stop light switch assembly remains on while the vehicle is driven in a GO (30 km/h (19 mph) or more) and STOP (less than 3 km/h (2 mph)) pattern 5 times.	Short in stop light switch signal circuit Stop light switch assembly ECM	Comes on	DTC stored	SAE Code: P0724