DTC P0703-12: Brake Switch "B" Circuit Short to Battery [10/2022 - ]: Description
WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
The stop light switch assembly is part of a duplex system that transmits two signals: STP and ST1-. These two 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 assembly remains on. When the stop light switch assembly remains on during "STOP and GO" driving, the ECM interprets this as a fault in the stop light switch assembly. The ECM stores the DTC.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | DTC Output from | Priority | Note |
|---|---|---|---|---|---|---|---|
| P0703-12 | Brake Switch "B" Circuit Short to Battery | The stop light switch assembly remains on even when 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). |
|
Does not come on | Engine | A |
|