Circuit Description
WARNING: This page is about a different car, the 2003 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Brake switch may also be referred to as stop light switch.
In this system, the signal of the stop light switch is used to judge whether the acceleration system is abnormal or not. The stop light switch has a duplex system (signals STP and ST1-) to memorize the abnormality when the signals of depressing and releasing the brake pedal are detected simultaneously. For normal condition, see BRAKE SWITCH NORMAL CONDITION table. DTC will set when ignition switch is on, brake pedal is released and STP signal is off while ST1- signal is off for .5 seconds or more. Possible causes are:
- Short in stop light switch signal circuit.
- Defective stop light switch.
- Defective ECM.
BRAKE SWITCH NORMAL CONDITION
| Signal | Brake Pedal Released | In Transition | Brake Pedal Depressed |
|---|---|---|---|
| STP | OFF | ON | ON |
| ST1- | ON | ON | OFF |