Last Modified: 04-05-2023 |
6.11:8.1.0 |
Doc ID: RM100000000VIH9 |
Model Year Start: 2016 |
Model: Sienna |
Prod Date Range: [12/2015 - 08/2016] |
Title: CRUISE CONTROL: CRUISE CONTROL SYSTEM: P0571; Brake Switch "A" Circuit; 2016 MY Sienna [12/2015 - 08/2016] |
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 seconds or more
|
-
Stop light switch
-
Stop light switch circuit
-
ECM
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
(a) Confirm vehicle type.
Result
Result
|
Proceed to
|
for Bulb Type Stop Light
|
A
|
for LED Type Stop Light
|
B
|
A
|
|
|
2.
|
CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - POWER SOURCE)
|
(a) Disconnect the stop light switch connector.
|
|
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Switch Condition
|
Specified Condition
|
A58-2 - Body ground
|
Always
|
11 to 14 V
|
A58-4 - Body ground
|
Ignition switch ON
|
11 to 14 V
|
Text in Illustration
*a
|
Front view of wire harness connector
(to Stop Light Switch)
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
3.
|
INSPECT STOP LIGHT SWITCH
|
(a) Remove the stop light switch (See page
).
(b) Inspect the stop light switch (See page
).
OK
|
|
|
4.
|
CHECK HARNESS AND CONNECTOR (ECM - STOP LIGHT SWITCH)
|
(a) Disconnect the A39 ECM connector.
(b) Disconnect the A58 stop light switch connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A39-36 (STP) - A58-1
|
Always
|
Below 1 Ω
|
A39-35 (ST1-) - A58-3
|
Always
|
Below 1 Ω
|
A39-36 (STP) or A58-1 - Body ground
|
Always
|
10 kΩ or higher
|
A39-35 (ST1-) or A58-3 - Body ground
|
Always
|
10 kΩ or higher
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
5.
|
CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - POWER SOURCE)
|
(a) Disconnect the stop light switch connector.
|
|
(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Switch Condition
|
Specified Condition
|
A59-1 (B) - Body Ground
|
Always
|
11 to 14 V
|
A59-5 (B) - Body ground
|
Ignition switch ON
|
11 to 14 V
|
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A59-3 (GND) - Body ground
|
Always
|
Below 1 Ω
|
Text in Illustration
*a
|
Front view of wire harness connector
(to Stop Light Switch)
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
6.
|
CHECK HARNESS AND CONNECTOR (ECM - STOP LIGHT SWITCH)
|
(a) Disconnect the A39 ECM connector.
(b) Disconnect the A59 stop light switch connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
A39-35 (ST1-) - A59-4 (L)
|
Always
|
Below 1 Ω
|
A39-36 (STP) - A59-2 (L)
|
Always
|
Below 1 Ω
|
A39-35 (ST1-) or A59-4 (L) - Body ground
|
Always
|
10 kΩ or higher
|
A39-36 (STP) or A59-2 (L) - Body ground
|
Always
|
10 kΩ or higher
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
7.
|
REPLACE STOP LIGHT SWITCH
|
(a) Replace the stop light switch (See page
).
NEXT
|
|
|
8.
|
CHECK FOR DTCS (CRUISE CONTROL SYSTEM)
|
(a) Clear the DTCs (See page
).
(b) Perform the following to make sure that the DTC detection conditions are met.
HINT:
If the detection conditions are not met, the malfunction cannot be detected.
(1) Turn the cruise control system on using the cruise control switch (ON/OFF button).
(c) Check for DTCs (See page
).
Result
Result
|
Proceed to
|
DTC P0571 is not output
|
A
|
DTC P0571 is output
|
B
|
A |
|
END (STOP LIGHT SWITCH WAS DEFECTIVE)
|
|