Toyota Sienna Quiz
Cruise control

Stop Light Switch Circuit Malfunction

In this manual: Cruise control
Introduction — 55Service specifications — 7Maintenance — 7Engine — 264U151e automatic transaxle — 108Transfer — 19Propeller shaft — 8Drive shaft — 14Differential — 16Axle — 18Suspension — 37Tire and wheel — 54Brake control — 141Parking brake — 16Steering Column — 11Power steering — 18Air conditioning — 106Supplemental restraint system — 146Seat belt — 22Theft deterrent — 14Engine immobiliser — 17Cruise control — 65Lighting — 61Wiper and washer — 13Door lock — 42Meter — 28Audio / visual — 94Navigation — 108Park assist / monitoring — 33Horn — 5Garage door opener — 42GR-FE Engine control system — 126Supplemental restraint system — 147Other system — 14Windshield / windowglass — 43Mirror — 23Instrument panel — 6Seat belt — 22Seat — 92Engine hood / door — 104Exterior — 39Interior — 5Sliding roof — 9Multiplex communication — 18Can communication — 23
8steps
~48min
2/5difficulty
Done 0 of 8

DTC P0571 Stop Light Switch Circuit Malfunction

DESCRIPTION

The ECM receives the brake demand signal from the distance control ECU and transmits it to the skid control ECU (brake actuator assembly).

The skid control ECU (brake actuator assembly) receives a signal from the ECM and operates the brake actuator.

The skid control ECU (brake actuator assembly) operates the brake actuator and illuminates the stop light by operating the BRK relay at the same time.

DTC No.

DTC Detection Condition

Trouble Area

P0571

 This trouble code is output when the ECM detected the BRK relay error signal from the skid control ECU for 0.2 sec. or more while the dynamic cruise control is in operation.
  • BRK relay
  • BRK relay circuit
  • Skid control ECU

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK BRK RELAY

CHECK BRK RELAY
  1. Remove the BRK relay from the Relay Block No. 6.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance
  1. Apply battery voltage between terminals 1 and 2.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

2 CHECK HARNESS AND CONNECTOR (BRK RELAY - BATTERY)

  1. Disconnect the connector from the Relay Block No. 6.
  2. Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

3 CHECK HARNESS AND CONNECTOR (BRK RELAY - SKID CONTROL ECU)

CHECK HARNESS AND CONNECTOR (BRK RELAY - SKID CONTROL ECU)
  1. Disconnect the S3 connector from the skid control ECU.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

REPLACE BRAKE ACTUATOR ASSEMBLY

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