DTC P0571 [MTX, LF ATX (FS5A-EL)]

id0102b4809000

DTC P0571

Brake switch circuit problem
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 is detected.
Diagnostic support note
•  This is a continuous monitor (Other).
•  The MIL does not illuminate.
•  FREEZE FRAME DATA is not available.
•  DTC is stored in PCM memory.
POSSIBLE CAUSE
•  Brake switch malfunction
•  Open circuit between brake switch terminal B and instrument cluster terminal 2M
•  Open circuit between brake switch terminal C and body ground
•  Short to power between brake switch terminal B and instrument cluster terminal 2M
•  Short to ground circuit between brake switch terminal B and instrument cluster terminal 2M
•  Communication error between PCM and instrument cluster
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record FREEZE FRAME DATA on repair, then go to the next step.
2
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.
3
VERIFY DTC FOR MODULE COMMUNICATION
•  Connect M-MDS to DLC-2.
•  Turn the ignition switch to the ON position (Engine off).
•  Verify stored DTC.
•  Is DTC U0155 stored?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[MTX, LF ATX (FS5A-EL)].)
No
Go to the next step.
4
VERIFY RELATED PENDING CODE OR STORED DTC
•  Turn the ignition switch off then to the ON position (Engine off).
•  Verify the related PENDING CODE or stored DTCs.
•  Is the DTC P0703 also present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[MTX, LF ATX (FS5A-EL)].)
No
Go to the next step.
5
INSPECT BRAKE SWITCH CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch off.
•  Disconnect the brake switch connector.
•  Inspect for poor connection (such as damaged, pull-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 12.
No
Go to the next step.
6
INSPECT BRAKE SWITCH
•  Inspect the brake switch.
•  Is the brake switch normal?
Yes
Go to the next step.
No
Replace brake switch, then go to Step 12.
7
INSPECT GROUND CIRCUIT OF BRAKE SWITCH NO.2 FOR OPEN CIRCUIT
•  Inspect for continuity between brake switch terminal C and body ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit, then go to Step 12.
8
INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH NO.2 FOR SHORT TO GROUND
•  Inspect for continuity between brake switch terminal B and body ground.
•  Is there continuity?
Yes
Repair or replace the wiring harness for short to ground circuit, then go to Step 12.
No
Go to the next step.
9
INSPECT INSTRUMENT CLUSTER CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch off.
•  Disconnect instrument cluster connector.
•  Inspect for poor connection (such as damaged, pull-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 12.
No
Go to the next step.
10
INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH NO.2 FOR OPEN CIRCUIT
•  Inspect for continuity between brake switch terminal B and instrument cluster terminal 2M.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit, then go to Step 12.
11
INSPECT SIGNAL CIRCUIT OF BRAKE SWITCH NO.2 FOR SHORT TO POWER
•  Turn the ignition switch to the ON position (Engine off).
•  Measure the voltage between brake switch terminal B and body ground.
•  Is the voltage B+?
Yes
Repair or replace the wiring harness for short to power circuit, then go to the next step.
No
Go to the next step.
12
VERIFY TROUBLESHOOTING OF P0571 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Turn the ignition switch to the ON position (Engine off).
•  Depress and release the brake pedal more than 5 times.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION[LF, L3].)
No
Go to the next step.
13
VERIFY AFTER REPAIR PROCEDURE
•  Perform “AFTER REPAIR PROCEDURE”.
•  Is any DTC present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[MTX, LF ATX (FS5A-EL)].)
No
Troubleshooting completed.