DTC P0703:00

Brake switch input circuit problem

DETECTION CONDITION

• The brake switch does not switch even though the vehicle is stopped 8 times repeatedly from a vehicle speed of 30 km/h {19 mph} or more.

Diagnostic support note

• This is a continuous monitor (CCM).

• The check engine light 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.

• DTC is stored in the PCM memory.

FAIL-SAFE FUNCTION

Not applicable

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 MAIN 200 A fuse and brake switch terminal A

• MAIN 200 A fuse and/or STOP 10 A fuse malfunction

• Open circuit in wiring harness between battery positive terminal and brake switch terminal A

• Short to ground in wiring harness between brake switch terminal D and PCM terminal 2G

• PCM connector or terminals malfunction

• Short to power supply in wiring harness between brake switch terminal D and PCM terminal 2G

• Open circuit in wiring harness between brake switch terminal D and PCM terminal 2G

• Brake switch No.1 malfunction

• PCM malfunction

STEP

INSPECTION

ACTION

1

• 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 Bulletins and/or on-line repair information availability.

• Is any related repair information available?

Yes

Perform repair or diagnosis according to the available repair information.

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

No

Go to the next step.

3

• Switch the ignition 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 9.

No

Go to the next step.

4

• Verify that the 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 MAIN 200 A fuse and STOP 10 A fuse.

• If the fuse is blown out:

• Refer to the wiring diagram and verify whether or not there is a common connector between MAIN 200 A fuse and brake switch terminal A.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to ground.

• Replace the fuse.

• If the fuse is damaged:

• Replace the fuse.

• If all fuses are normal:

• Refer to the wiring diagram and verify whether or not there is a common connector between battery positive terminal and brake switch terminal A.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has an open circuit.

Go to Step 9.

5

• Verify that the 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 in the wiring harness:

• Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and PCM terminal 2G.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to ground.

If the short to ground circuit could not be detected in the wiring harness:

• Replace the PCM (short to ground in the PCM internal circuit).

  (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

Go to Step 9.

No

Go to the next step.

6

• 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 9.

No

Go to the next step.

7

• Verify that the brake switch and PCM connectors are disconnected.

• Switch the ignition ON (engine off).

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

• Is the voltage 0 V?

Yes

Go to the next step.

No

Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and PCM terminal 2G.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to power supply.

Go to Step 9.

8

• Verify that the brake switch and PCM connectors are disconnected.

• Switch the ignition off.

• Inspect for continuity between brake switch terminal D (wiring harness-side) and PCM terminal 2G (wiring harness-side).

• Is there continuity?

Yes

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

(See BRAKE PEDAL REMOVAL/INSTALLATION.)

No

Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and PCM terminal 2G.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has an open circuit.

Go to the next step.

9

• Always reconnect all disconnected connectors.

• Clear the DTC from the PCM memory using the M-MDS.

  (See AFTER REPAIR PROCEDURE [SKYACTIV-G 2.5].)

• Drive the vehicle.

• Repeat deceleration 8 times under both of the following conditions:

• Vehicle speed: from above 30 km/h {19 mph} to 30 km/h {19 mph} or less

• Deceleration rate: exceeds 2.4 km/h {1.5 mph} per sec

• Perform the Pending Trouble Code Access Procedure.

  (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.5].)

• Is the PENDING CODE for this DTC present?

Yes

Repeat the inspection from Step 1.

• If the malfunction recurs, replace the PCM.

  (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

Go to the next step.

No

Go to the next step.

10

• Perform the “AFTER REPAIR PROCEDURE”.

  (See AFTER REPAIR PROCEDURE [SKYACTIV-G 2.5].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [SKYACTIV-G 2.5].)

No

DTC troubleshooting completed.