DTC P0703:00 [MZR 1.8, MZR 2.0, MZR 2.5]

id0102f4706500

DTC P0703:00

Brake switch input circuit problem
DETECTION CONDITION
•  The PCM monitors the input signal from the brake switch No.1. If the input signal does not change while following decelerating 8 times, the PCM determines that there is a brake switch No.1 input circuit problem.
MONITORING CONDITIONS
―  Vehicle speed: become from above 30 km/h {19 mph}to 30 km/h {19 mph} or less
―  Deceleration rate: exceeds 3.8 km/h {2.4 mph} per 0.1 s
Diagnostic support note
•  This is a continuous monitor (CCM).
•  The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
•  PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle.
•  FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
Caution
•  Inspect the brake switch with it installed to the brake pedal, otherwise the brake switch may not operate normally. If the brake switch is removed from the brake pedal, replace the brake switch with a new one.
•  Brake switch connector or terminals malfunction
•  Short to ground or open circuit in brake switch No.1 power supply circuit
―  Short to ground in wiring harness between STOP 10 A fuse and brake switch terminal A
―  STOP 10 A fuse malfunction
―  Open circuit in wiring harness between battery positive terminal and brake switch terminal A
•  ABS HU/CM or DSC HU/CM connector or terminals malfunction
•  Short to ground in wiring harness between the following terminals:
―  Brake switch terminal D—ABS HU/CM terminal N (Vehicles without DSC)
―  Brake switch terminal D—DSC HU/CM terminal C (Vehicles with DSC)
―  Brake switch terminal D—PCM terminal 1AB
•  PCM connector or terminals malfunction
•  Short to power supply in wiring harness between the following terminals:
―  Brake switch terminal D—ABS HU/CM terminal N (Vehicles without DSC)
―  Brake switch terminal D—DSC HU/CM terminal C (Vehicles with DSC)
―  Brake switch terminal D—PCM terminal 1AB
•  Open circuit in wiring harness between brake switch terminal D and PCM terminal 1AB
•  ABS HU/CM or DSC HU/CM malfunction
•  Brake switch malfunction
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA (Mode 2)/snapshot data been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (Mode 2)/snapshot data on the repair order, 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
INSPECT BRAKE SWITCH CONNECTOR CONDITION
•  Switch the ignition to off.
•  Disconnect the brake switch connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 11.
No
Go to the next step.
4
INSPECT BRAKE SWITCH NO.1 POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
•  Brake switch connector is disconnected.
•  Measure the voltage at the brake switch terminal A (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 11.
5
INSPECT ABS HU/CM OR DSC HU/CM CONNECTOR CONDITION
•  Disconnect the ABS HU/CM or DSC HU/CM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 11.
No
Go to the next step.
6
INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Brake switch connector is disconnected.
•  ABS HU/CM connector is disconnected. (vehicles without DSC)
•  DSC HU/CM connector is disconnected. (vehicles with DSC)
•  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 the PCM internal circuit).
Go to Step 11.
No
Go to the next step.
7
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 11.
No
Go to the next step.
8
INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Brake switch and PCM connectors are disconnected.
•  ABS HU/CM connector is disconnected. (vehicles without DSC)
•  DSC HU/CM connector is disconnected. (vehicles with DSC)
•  Switch the ignition to ON (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 11.
No
Go to the next step.
9
INSPECT BRAKE SWITCH NO.1 SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Brake switch and PCM connectors are disconnected.
•  ABS HU/CM connector is disconnected. (vehicles without DSC)
•  DSC HU/CM connector is disconnected. (vehicles with DSC)
•  Switch the ignition to off.
•  Inspect for continuity between brake switch terminal D (wiring harness-side) and PCM terminal 1AB (wiring harness-side).
•  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 11.
10
INSPECT ABS HU/CM OR DSC HU/CM
•  Reconnect all disconnected connectors.
•  Switch the ignition to ON (engine off).
•  Measure the voltage at the ABS HU/CM terminal N (wiring harness-side). (Vehicles without DSC)
•  Measure the voltage at the DSC HU/CM terminal C (wiring harness-side). (Vehicles with DSC)
•  Is the voltage normal?
Yes
Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION.)
No
Vehicles without DSC:
•  Replace the ABS HU/CM, then go to the next step.
Vehicles with DSC:
•  Replace the DSC HU/CM, then go to the next step.
11
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Drive the vehicle.
•  Repeat deceleration 8 times under both of the following conditions:
―  Vehicle speed: become from above 30 km/h {19 mph}to 30 km/h {19 mph} or less
―  Deceleration rate: exceeds 3.8 km/h {2.4 mph} per 0.1 s
•  Perform the Pending Trouble Code Access Procedure.
•  Is the PENDING CODE for this DTC present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [MZR 1.8, MZR 2.0, MZR 2.5].)
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 1.8, MZR 2.0, MZR 2.5].)
No
DTC troubleshooting completed.