DTC P0571:00 [L3 Turbo]

DTC P0571:00	Brake switch circuit malfunction
DETECTION CONDITION	• The PCM monitors switching in conjunction with brake switches No.1 and No.2. If either No.1 or No.2 do not switch for a continuous five times even though either No.1 or No.2 is switched from off to on or from on to off, P0571:00 is detected. Diagnostic support note • This is a continuous monitor (other). • The MIL does not illuminate. • FREEZE FRAME DATA (Mode 2)/Snapshot data is not available. • DTCs are stored in the PCM memory.
POSSIBLE CAUSE	• Brake switch connector or terminals malfunction • Brake switch malfunction • Short to ground or open circuit in brake switch power supply circuit ― Short to ground in wiring harness between battery positive terminal and brake switch terminal B ― STOP 10 A fuse malfunction ― Open circuit in wiring harness between battery positive terminal and brake switch terminal B • Short to ground in wiring harness between brake switch terminal D and PCM terminal 1AB • PCM connector or terminals malfunction • Short to power supply in wiring harness between brake switch terminal D and PCM terminal 1AB • Open circuit in wiring harness between brake switch terminal D and PCM terminal 1AB • Open circuit in wiring harness between brake switch terminal C and body ground • Short to ground in wiring harness between brake switch terminal A and PCM terminal 1AF • Short to power supply in wiring harness between brake switch terminal A and PCM terminal 1AF • Open circuit in wiring harness between brake switch terminal A and PCM terminal 1AF • PCM malfunction

DTC P0571:00

Brake switch circuit malfunction

DETECTION CONDITION

• The PCM monitors switching in conjunction with brake switches No.1 and No.2. If either No.1 or No.2 do not switch for a continuous five times even though either No.1 or No.2 is switched from off to on or from on to off, P0571:00 is detected.

Diagnostic support note

• This is a continuous monitor (other).

• The MIL does not illuminate.

• FREEZE FRAME DATA (Mode 2)/Snapshot data is not available.

• DTCs are stored in the PCM memory.

POSSIBLE CAUSE

• Brake switch connector or terminals malfunction

• Brake switch malfunction

• Short to ground or open circuit in brake switch power supply circuit

― Short to ground in wiring harness between battery positive terminal and brake switch terminal B

― STOP 10 A fuse malfunction

― Open circuit in wiring harness between battery positive terminal and brake switch terminal B

• Short to ground in wiring harness between brake switch terminal D and PCM terminal 1AB

• PCM connector or terminals malfunction

• Short to power supply in wiring harness between brake switch terminal D and PCM terminal 1AB

• Open circuit in wiring harness between brake switch terminal D and PCM terminal 1AB

• Open circuit in wiring harness between brake switch terminal C and body ground

• Short to ground in wiring harness between brake switch terminal A and PCM terminal 1AF

• Short to power supply in wiring harness between brake switch terminal A and PCM terminal 1AF

• Open circuit in wiring harness between brake switch terminal A and PCM terminal 1AF

• PCM malfunction

STEP	INSPECTION	ACTION
1	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available?	Yes	Perform repair or diagnosis according to the available Service Information. • If the vehicle is not repaired, go to the next step.
No	Go to the next step.
2	VERIFY RELATED PENDING CODE AND STORED DTC • Turn the ignition switch off, then to the ON position (engine off). • Perform the Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Is the DTC P0703:00 also present?	Yes	Go to the applicable DTC inspection. (See DTC P0703:00 [L3 Turbo].)
No	Go to the next step.
3	INSPECT BRAKE SWITCH CONNECTOR CONDITION • Turn the ignition switch off. • Disconnect the brake switch connector. • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 16.
No	Go to the next step.
4	INSPECT BRAKE SWITCH • Inspect the brake switch. (See BRAKE SWITCH INSPECTION.) • Is there any malfunction?	Yes	Replace the brake switch, then go to Step 16. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
No	Go to the next step.
5	INSPECT WHETHER MALFUNCTION IS BRAKE SWITCH NO.1 OR BRAKE SWITCH NO.2 • Reconnect all disconnected connectors. • Access the BOO PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Monitor the BOO PID while the brake pedal is pressed and released. • Does the BOO PID change according to brake pedal condition?	Yes	Go to Step 11.
No	Go to the next step.
6	INSPECT BRAKE SWITCH NO.1 POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT • Turn the ignition switch off. • Disconnect the brake switch connector. • Measure the voltage at the brake switch terminal B (wiring harness-side). • Is the voltage B+?	Yes	Go to the next step.
No	Inspect the STOP 10 A fuse. • If the fuse is melt: ― Repair or replace the wiring harness for a possible short to ground. ― Replace the fuse. • If the fuse is deterioration: ― Replace the fuse. • If the fuse is normal: ― Repair or replace the wiring harness for a possible open circuit. Go to Step 16.
7	INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO GROUND • Brake switch connector is disconnected. • Inspect for continuity between brake switch terminal D (wiring harness-side) and body ground. • Is there continuity?	Yes	If the short to ground circuit could be detected: • Repair or replace the wiring harness for a possible short to ground. If the short to ground circuit could not be detected: • Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION [L3 Turbo].) Go to Step 16.
No	Go to the next step.
8	INSPECT PCM CONNECTOR CONDITION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 16.
No	Go to the next step.
9	INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY • Brake switch and PCM connectors are disconnected. • Turn the ignition switch to the ON position (engine off). • Measure the voltage at the brake switch terminal D (wiring harness-side). • Is there any voltage?	Yes	Repair or replace the wiring harness for a possible short to power supply, then go to Step 16.
No	Go to the next step.
10	INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR OPEN CIRCUIT • Brake switch and PCM connectors are disconnected. • Turn the ignition switch off. • Inspect for continuity between brake switch terminal D (wiring harness-side) and PCM terminal 1AB (wiring harness-side). • Is there continuity?	Yes	Replace the brake switch, then go to Step 16. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
No	Repair or replace the wiring harness for a possible open circuit, then go to Step 16.
11	INSPECT BRAKE SWITCH NO.2 GROUND CIRCUIT FOR OPEN CIRCUIT • Turn the ignition switch off. • Disconnect the brake switch connector. • Inspect for continuity between brake switch terminal C (wiring harness-side) and body ground. • Is there continuity?	Yes	Go to the next step.
No	Repair or replace the wiring harness for a possible open circuit, then go to Step 16.
12	INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR SHORT TO GROUND • Brake switch connector is disconnected. • Inspect for continuity between brake switch terminal A (wiring harness-side) and body ground. • Is there continuity?	Yes	If the short to ground circuit could be detected: • Repair or replace the wiring harness for a possible short to ground. If the short to ground circuit could not be detected: • Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION [L3 Turbo].) Go to Step 16.
No	Go to the next step.
13	INSPECT PCM CONNECTOR CONDITION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). • Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 16.
No	Go to the next step.
14	INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY • Brake switch and PCM connectors are disconnected. • Turn the ignition switch to the ON position (engine off). • Measure the voltage at the brake switch terminal A (wiring harness-side). • Is there any voltage?	Yes	Repair or replace the wiring harness for a possible short to power supply, then go to Step 16.
No	Go to the next step.
15	INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR OPEN CIRCUIT • Brake switch and PCM connectors are disconnected. • Turn the ignition switch off. • Inspect for continuity between brake switch terminal A (wiring harness-side) and PCM terminal 1AF (wiring harness-side). • Is there continuity?	Yes	Replace the brake switch, then go to the next step. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
No	Repair or replace the wiring harness for a possible open circuit, then go to the next step.
16	VERIFY DTC TROUBLESHOOTING COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [L3 Turbo].) • Turn the ignition switch to the ON position (engine off). • Depress and release the brake pedal for 15 s more than 5 times. • Perform the DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Is the same DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
17	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [L3 Turbo].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No	DTC troubleshooting completed.

STEP

INSPECTION

ACTION

VERIFY RELATED SERVICE INFORMATION AVAILABILITY

• Verify related Service Information availability.

• Is any related Service Information available?

Yes

Perform repair or diagnosis according to the available Service Information.

• If the vehicle is not repaired, go to the next step.

Go to the next step.

VERIFY RELATED PENDING CODE AND STORED DTC

• Turn the ignition switch off, then to the ON position (engine off).

• Perform the Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Is the DTC P0703:00 also present?

Yes

Go to the applicable DTC inspection.

(See DTC P0703:00 [L3 Turbo].)

Go to the next step.

INSPECT BRAKE SWITCH CONNECTOR CONDITION

• Turn the ignition switch off.

• Disconnect the brake switch connector.

• Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).

• Is there any malfunction?

Yes

Repair or replace the connector and/or terminals, then go to Step 16.

Go to the next step.

INSPECT BRAKE SWITCH

• Inspect the brake switch. (See BRAKE SWITCH INSPECTION.)

• Is there any malfunction?

Yes

Replace the brake switch, then go to Step 16.

(See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].)

(See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)

Go to the next step.

INSPECT WHETHER MALFUNCTION IS BRAKE SWITCH NO.1 OR BRAKE SWITCH NO.2

• Reconnect all disconnected connectors.

• Access the BOO PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Monitor the BOO PID while the brake pedal is pressed and released.

• Does the BOO PID change according to brake pedal condition?

Yes

Go to Step 11.

Go to the next step.

INSPECT BRAKE SWITCH NO.1 POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT

• Turn the ignition switch off.

• Disconnect the brake switch connector.

• Measure the voltage at the brake switch terminal B (wiring harness-side).

• Is the voltage B+?

Yes

Go to the next step.

Inspect the STOP 10 A fuse.

• If the fuse is melt:

― Repair or replace the wiring harness for a possible short to ground.

― Replace the fuse.

• If the fuse is deterioration:

― Replace the fuse.

• If the fuse is normal:

― Repair or replace the wiring harness for a possible open circuit.

Go to Step 16.

INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO GROUND

• Brake switch connector is disconnected.

• Inspect for continuity between brake switch terminal D (wiring harness-side) and body ground.

• Is there continuity?

Yes

If the short to ground circuit could be detected:

• Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:

• Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION [L3 Turbo].)

Go to Step 16.

Go to the next step.

INSPECT PCM CONNECTOR CONDITION

• Disconnect the PCM connector.

• Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).

• Is there any malfunction?

Yes

Repair or replace the connector and/or terminals, then go to Step 16.

Go to the next step.

INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY

• Brake switch and PCM connectors are disconnected.

• Turn the ignition switch to the ON position (engine off).

• Measure the voltage at the brake switch terminal D (wiring harness-side).

• Is there any voltage?

Yes

Repair or replace the wiring harness for a possible short to power supply, then go to Step 16.

Go to the next step.

INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR OPEN CIRCUIT

• Brake switch and PCM connectors are disconnected.

• Turn the ignition switch off.

• Inspect for continuity between brake switch terminal D (wiring harness-side) and PCM terminal 1AB (wiring harness-side).

• Is there continuity?

Yes

Replace the brake switch, then go to Step 16.

(See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].)

(See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)

Repair or replace the wiring harness for a possible open circuit, then go to Step 16.

INSPECT BRAKE SWITCH NO.2 GROUND CIRCUIT FOR OPEN CIRCUIT

• Turn the ignition switch off.

• Disconnect the brake switch connector.

• Inspect for continuity between brake switch terminal C (wiring harness-side) and body ground.

• Is there continuity?

Yes

Go to the next step.

Repair or replace the wiring harness for a possible open circuit, then go to Step 16.

INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR SHORT TO GROUND

• Brake switch connector is disconnected.

• Inspect for continuity between brake switch terminal A (wiring harness-side) and body ground.

• Is there continuity?

Yes

If the short to ground circuit could be detected:

• Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:

• Replace the PCM (short to ground in PCM internal circuit). (See PCM REMOVAL/INSTALLATION [L3 Turbo].)

Go to Step 16.

Go to the next step.

INSPECT PCM CONNECTOR CONDITION

• Disconnect the PCM connector.

• Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).

• Is there any malfunction?

Yes

Repair or replace the connector and/or terminals, then go to Step 16.

Go to the next step.

INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY

• Brake switch and PCM connectors are disconnected.

• Turn the ignition switch to the ON position (engine off).

• Measure the voltage at the brake switch terminal A (wiring harness-side).

• Is there any voltage?

Yes

Repair or replace the wiring harness for a possible short to power supply, then go to Step 16.

Go to the next step.

INSPECT BRAKE SWITCH NO.2 SIGNAL CIRCUIT FOR OPEN CIRCUIT

• Brake switch and PCM connectors are disconnected.

• Turn the ignition switch off.

• Inspect for continuity between brake switch terminal A (wiring harness-side) and PCM terminal 1AF (wiring harness-side).

• Is there continuity?

Yes

Replace the brake switch, then go to the next step.

(See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].)

(See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)

Repair or replace the wiring harness for a possible open circuit, then go to the next step.

VERIFY DTC TROUBLESHOOTING COMPLETED

• Make sure to reconnect all disconnected connectors.

• Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [L3 Turbo].)

• Turn the ignition switch to the ON position (engine off).

• Depress and release the brake pedal for 15 s more than 5 times.

• Perform the DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Is the same DTC present?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

VERIFY AFTER REPAIR PROCEDURE

• Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [L3 Turbo].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [L3 Turbo].)

DTC troubleshooting completed.