P0571

CRUISE CONTROL: CRUISE CONTROL SYSTEM: P0571: Brake Switch "A" Circuit
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.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - BATTERY)

(a) Disconnect the A22 connector from the stop light switch.





(b) Measure the voltage according to the value(s) in the table below

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

2. INSPECT STOP LIGHT SWITCH

(a) Remove stop light switch. Removal





(b) Measure the resistance according to the value(s) in the table below.

Standard resistance:





(c) Install the stop light switch.

NG -- REPLACE STOP LIGHT SWITCH Removal
OK -- Continue to next step.

3. CHECK ECM

(a) Reconnect the stop light switch connector.





(b) Disconnect the A5 and A6 connectors from the ECM.

(c) Turn the engine switch on (IG).

(d) Measure the voltage according to the value(s) in the table below.

Standard voltage:





Result:





B -- REPLACE ECM (2GR-FSE) Removal

C -- REPLACE ECM (4GR-FSE) Removal

A -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - ECM)