Dtc P0571/52 Stop Light Switch Circuit

Cruise Control System. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
Cruise Control. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (STOP, IGN, IG2)

INSPECT IG2 RELAY

INSPECT STOP LIGHT SWITCH

CHECK WIRE HARNESS (SWITCH - BATTERY)

CHECK WIRE HARNESS (ECM - BATTERY)

DTC P0571/52 Stop Light Switch Circuit


DESCRIPTION

While driving with the cruise control, if the ECM detects that the brake pedal is depressed, the cruise control operation will be canceled. The stop light switch sends brake pedal status signals to the ECM. When the brake pedal is not depressed, terminal ST1- is equal to the positive (+) battery voltage and terminal STP is below 1 V. When the brake pedal is depressed, the ECM cancels cruise control operation. The ECM outputs this DTC when the voltage of terminals ST1- and STP are both below 1 V for 0.5 seconds or more at the same time. The fail-safe function operates to enable normal driving even if there is a malfunction in the stop light signal circuit.

DTC Code
DTC Detection Condition
Trouble Area
P0571/52
ECM detects malfunction of stop light switch circuit under both of following conditions:
  1. Voltage of terminal STP is less than 1 V for 0.5 seconds or more
  2. Voltage of terminal ST1- is less than 1 V for 0.5 seconds or more
  1. Stop light switch
  2. Wire harness
  3. ECM

WIRING DIAGRAM


Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Cruise Control.Cruise Control System. Dtc P0571/52 Stop Light Switch Circuit


INSPECTION PROCEDURE

1.INSPECT FUSE (STOP, IGN, IG2)

  1. Remove the STOP and IGN fuses from the instrument panel junction block.

  1. Remove the IG2 fuse from the engine room No. 1 relay block.

  1. Measure the resistance of the fuses.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


2.INSPECT IG2 RELAY
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Cruise Control.Cruise Control System. Dtc P0571/52 Stop Light Switch Circuit

  1. Remove the IG2 relay from the instrument panel junction block.

  1. Measure the resistance of the relay.

    Standard resistance:
    Tester Connection
    		 Specified Condition
    3 - 5
    		10 kΩ or higher
    Below 1 Ω
    (when battery voltage is applied to terminals 1 and 2)


NG
REPLACE IG2 RELAY
OK


3.INSPECT STOP LIGHT SWITCH
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Cruise Control.Cruise Control System. Dtc P0571/52 Stop Light Switch Circuit

  1. Remove the stop light switch.

  1. Measure the resistance of the switch.

    Standard resistance:
    Tester Connection
    		Switch Condition
    		 Specified Condition
    1 - 2
    		Not pushed
    		Below 1 Ω
    3 - 4
    		Pushed
    1 - 2
    		Pushed
    		10 kΩ or higher
    3 - 4
    		Not pushed


NG
REPLACE STOP LIGHT SWITCH
OK


4.CHECK WIRE HARNESS (SWITCH - BATTERY)


    Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Cruise Control.Cruise Control System. Dtc P0571/52 Stop Light Switch Circuit

  1. Disconnect the A66 switch connector.

  1. Measure the voltage of the wire harness side connector.

    Standard voltage:
    Tester Connection
    		Switch Condition
    		 Specified Condition
    A66-2 - Body ground
    		Always
    		11 to 14 V
    A66-4 - Body ground
    		Ignition switch ON


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


5.CHECK WIRE HARNESS (ECM - BATTERY)
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Cruise Control.Cruise Control System. Dtc P0571/52 Stop Light Switch Circuit

  1. Disconnect the A12 ECM connector.

  1. Turn the ignition switch ON.

  1. Measure the voltage of the wire harness side connector.

    Standard voltage:
    Tester Connection
    		Switch Condition
    		 Specified Condition
    A12-35 (ST1-) - Body ground
    		Depressed
    		11 to 14 V
    A12-36 (STP) - Body ground
    		Released
    A12-35 (ST1-) - Body ground
    		Released
    		Below 1 V
    A12-36 (STP) - Body ground
    		Depressed


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE ECM