P0571

DTC P0571 Brake Switch "A" Circuit

CIRCUIT DESCRIPTION

DTC Detection Condition:

When the brake pedal is depressed, the stop light switch sends a signal to ECM. When ECM receives this signal, it cancels the cruise control.

A fail-safe function is provided so that the cruise control is canceled normally when there is a malfunction in the stop light signal circuit.

The cancellation occurs when the battery positive voltage is applied to terminal STP, ST1-.

When the brake is ON, battery positive voltage is applied to terminal STP, ST1- of the ECM via the stop fuse and the stop light switch, and then the ECM turns the cruise control OFF

Even if the harness connected to terminal STP, ST1- has an open circuit, the cruise control will be turned OFF.

Wiring Diagram:

Step 1 - 2:

Step 3 - 4:

INSPECTION PROCEDURE

HINT: In case of using the hand-held tester, start the inspection from step 1 and in case of not using the hand-held tester, start from step 2.