DTC P0571 Brake Switch "A" Circuit
DESCRIPTION
When the brake pedal is depressed, the stop light switch sends a signal to the ECM. When the ECM receives this signal, it cancels the cruise control. The fail-safe function operates to enable normal driving even if there is a malfunction in the stop light signal circuit. The cancellation condition occurs when voltage is applied to terminal STP. When the brake is applied, voltage is normally applied to terminal STP of the ECM through the STOP SW fuse and the stop light switch, and the ECM turns the cruise control off.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|
P0571 |
Voltage of STP terminal and that of ST1- terminal of ECM are less than 1 V for 0.5 sec. or more |
|
WIRING DIAGRAM

INSPECTION PROCEDURE
1 READ VALUE OF INTELLIGENT TESTER
ECM (Cruise control):

OK: When the brake pedal is operated, the display changes as shown above.
REPLACE ECM
2 CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - BATTERY)

Standard voltage

3 INSPECT STOP LIGHT SWITCH

Standard resistance

4 CHECK ECM

Standard voltage

REPLACE ECM
Vehicle Speed Sensor Malfunction
Stop Light Switch Circuit MalfunctionСamshaft timing oil control valve assembly
COMPONENTS
ON-VEHICLE INSPECTION
1. INSPECT CAMSHAFT TIMING CONTROL VALVE ASSEMBLY
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Start the engine and warm it up.
(d) Select the intelligent tester from the ACTIVE TEST
...
On-vehicle inspection
1. INSPECT CAMSHAFT TIMING CONTROL VALVE ASSEMBLY
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Start the engine and warm it up.
Select the intelligent tester from the ACTIVE TEST
menu.
Check the engine speed ...
Closing the fuel tank cap
After refueling, turn the fuel tank
cap until you hear a click. Once
the cap is released, it will turn
slightly in the opposite direction.
WARNINGWhen replacing the fuel tank cap
Do not use anything but a genuine Toyota fuel tank cap designed for
your
vehicle. Doing so may c ...