DTC P0703-12: Brake Switch "B" Circuit Short to Battery [11/2016 - ]: Description

WARNING: This page is about a different car, the 2019 Toyota Highlander, 2018 Toyota Highlander, and 2017 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.

The purpose of the stop light switch signal 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	1. Diagnosis Condition 2. Malfunction Status 3. Malfunction Time 4. Other The ignition switch is ON and battery voltage is 8 V or more. The stop light switch remains on. 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 2-trip detection logic	Stop light switch assembly Short in stop light switch signal circuit ECM	Comes on	DTC stored	SAE Code: P0724