DTC Troubleshooting: P0571
DTC P0571: Brake Pedal Position Switch Circuit Malfunction
NOTE:
Before you troubleshoot, review the general troubleshooting information.
If the accelerator pedal is pressed with pressing the brake pedal lightly and continuously for 5 minutes or more, this DTC will be stored.

DTC Description
Confirmed DTC
Pending DTC
P0571 Brake Pedal Position Switch Circuit Malfunction
    

1.
Brake lights check 1:

Brake lights check 1
?1.
Check the brake lights without the brake pedal pressed.

Do the brake lights stay on?

     
YES
     
     
     
Go to step 9.
     
NO
     
     
     
Go to step 2.
2.
Brake lights check 2:

Brake lights check 2
?1.
Check the brake lights with the brake pedal pressed.

Do the brake lights come on?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
Go to step 5.
3.
Brake pedal position switch signal check:

Brake pedal position switch signal check
?1.
Turn the vehicle to the ON mode.

?2.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
BRAKE SWITCH
    

Does the signal change ON and OFF when the brake pedal is pressed and released?

     
YES
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the brake pedal position switch and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot.?
     
NO
     
     
     
Go to step 4.
4.
Open wire check (STOP SW line):

Open wire check (STOP SW line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Jump the SCS line with the HDS, and wait more than 1 minute.


?3.
Disconnect the following connector.
PCM connector A (50P)

?4.
Press the brake pedal, and measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector A (50P): disconnected
Brake pedal: pressed
Test point 1
PCM connector A (50P) No. 26
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The STOP SW wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P0571 goes away and the PCM was substituted, replace the original PCM.?
     
NO
     
     
     
Repair an open in the STOP SW wire between the PCM (A26) and the brake pedal position switch.?
5.
Brake pedal position switch check:

Brake pedal position switch check
?1.
Test the brake pedal position switch.

Is the brake pedal position switch normal?

     
YES
     
     
     
Go to step 6.
     
NO
     
     
     
6.
Fuse check:

Fuse check
?1.
Check the following fuse.
Fuse
No. A9 (10 A)
Location
Under-hood fuse/relay box

Is the fuse OK?

     
YES
     
     
     
Go to step 7.
     
NO
     
     
     
Replace the No. A9 (10 A) fuse. Also check for a short to ground on the No. A9 (10 A) fuse circuit if needed.?
7.
Open wire check (+B STOP line):

Open wire check (+B STOP line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
Test point 1
Brake pedal position switch 4P connector No. 2
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The +B STOP wire is OK. Go to step 8.
     
NO
     
     
     
Repair an open in the +B STOP wire between the No. A9 (10 A) fuse in the under-hood fuse/relay box and the brake pedal position switch.?
8.
Open wire check (STOP SW line):

Open wire check (STOP SW line)
?1.
Jump the SCS line with the HDS, and wait more than 1 minute.


?2.
Disconnect the following connector.
PCM connector A (50P)

?3.
Press the brake pedal, and measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
PCM connector A (50P): disconnected
Brake pedal: pressed
Test point 1
PCM connector A (50P) No. 26
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The STOP SW wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P0571 goes away and the PCM was substituted, replace the original PCM.?
     
NO
     
     
     
Repair an open in the STOP SW wire between the PCM (A26) and the brake pedal position switch.?
9.
Brake pedal position switch installation check:

Brake pedal position switch installation check
?1.
Remove the brake pedal position switch with the connector is connected.

?2.
Check the brake lights with the rod of the brake pedal position switch pressed.

Do the brake lights go off?

     
YES
     
     
     
The brake pedal position switch installation is incorrect, install the brake pedal position switch and adjust the pedal height.?
     
NO
     
     
     
Go to step 10.
10.
Brake pedal position switch check:

Brake pedal position switch check
?1.
Test the brake pedal position switch.

Is the brake pedal position switch normal?

     
YES
     
     
     
The brake pedal position switch is OK, repair a short to power in the STOP SW wire between the PCM (A26) and the brake pedal position switch.?
     
NO