DTC P0571

DTC P0571 : Brake Pedal Position Switch Circuit Malfunction

NOTE:

Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information .
If the brake pedal is pressed lightly and continuously for 5 minutes or more, this DTC will be stored.

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

DTC (PGM-FI)

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
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.

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
Signal	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.

Go to step 4.

Open wire check (STOP SW line)

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Jump the SCS line with the HDS.

-3. Disconnect the following connector.

PCM connector A (51P)

-4. Measure the voltage between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
Test condition	Brake pedal pressed
Test circuit	STOP SW
Test point 1	PCM connector A (51P) No. 25 (LT GRN)
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there battery voltage?

YES

The STOP SW wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then do the repair verification.

Repair an open in the STOP SW wire between the PCM (A25) and the brake pedal position switch, then do the repair verification.

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

Replace the brake pedal position switch , then do the repair verification.

Fuse check

-1. Check the following fuse.

Fuse	No. C19 (7.5 A)
Location	Under-hood fuse/relay box

Is the fuse OK?

YES

Go to step 7.

Replace the No. C19 (7.5 A) fuse. Also check for a short to ground on the No. C19 (7.5 A) fuse circuit if needed, then do the repair verification.

Open wire check (+B STOP line)

-1. Measure the voltage between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
Test circuit	+B STOP
Test point 1	Brake pedal position switch 4P connector No. 2 (PUR)
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there battery voltage?

YES

The +B STOP wire is OK. Go to step 8.

Repair an open in the +B STOP wire between the No. C19 (7.5 A) fuse in the under-hood fuse/relay box and the brake pedal position switch, then do the repair verification.

Open wire check (STOP SW line)

-1. Jump the SCS line with the HDS.

-2. Disconnect the following connector.

PCM connector A (51P)

-3. Measure the voltage between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
Test condition	Brake pedal pressed
Test circuit	STOP SW
Test point 1	PCM connector A (51P) No. 25 (LT GRN)
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there battery voltage?

YES

The STOP SW wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then do the repair verification.

Repair an open in the STOP SW wire between the PCM (A25) and the brake pedal position switch, then do the repair verification.

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 is OK, install the brake pedal position switch and adjust the pedal height , then do the repair verification.

NO

Go to step 10.
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 (A25) and the brake pedal position switch, then do the repair verification.

NO

Replace the brake pedal position switch , then do the repair verification.

Repair verification

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Reconnect all connectors.

-3. Exit the SCS mode with the HDS.

-4. Turn the vehicle to the ON mode.

-5. Reset the PCM with the HDS .

Reset PCM

-6. Do the PCM idle learn procedure .

-7. Turn the vehicle to the OFF (LOCK) mode.

-8. Turn the vehicle to the ON mode.

-9. Press the brake pedal several times.

-10.

Check for Pending or Confirmed DTCs with the HDS.

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

DTC (PGM-FI)

Is DTC P0571 indicated?

YES

Check for poor connections or loose terminals at the brake pedal position switch and the PCM. If the PCM was updated, substitute a known-good PCM , then recheck. If the PCM was substituted, go to step 1.

Troubleshooting is complete. If the PCM was substituted, replace the original PCM . If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.