DTC P0571 Brake Switch "A" Circuit: Description
When the brake pedal is depressed, the stop light switch sends a signal to the hybrid vehicle control ECU. Receiving the signal, the hybrid vehicle control ECU cancels the cruise control. Even if there is a malfunction in the stop light signal circuit while the cruise control is in operation, normal driving is maintained due to fail-safe function.
Cruise control is canceled when positive battery voltage is applied to terminal STP.
When the brake pedal is depressed, positive voltage is applied to terminal STP of the hybrid vehicle control ECU through the STOP fuse and the stop light switch, and the hybrid vehicle control ECU cancels the cruise control.
When the brake pedal is released, positive voltage is applied to terminal ST1- of the hybrid vehicle control ECU through the IGN fuse and the stop light switch, and the hybrid vehicle control ECU operates the cruise control.
HINT:
Inspect the fuses and relays before confirming the suspected areas which are shown in the table below.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0571 | Trouble code is output when voltages of terminals ST1- and STP of the hybrid vehicle control ECU are both below 1 V for 0.5 seconds or more |
|