DTC P0703 [ZJ, Z6]

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DTC P0703 [ZJ, Z6]

B3E010200700W01

DTC P0703 | Brake switch input circuit problem
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DETECTION CONDITION

• The PCM monitors the input signal from the brake switch. If the input signal does not change while following decelerating 8 times, the PCM determines that there is a brake switch input circuit problem.
MONITORING CONDITION

  - Vehicle speed is 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 the first drive cycle.
• FREEZE FRAME DATA is available.
• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Brake switch malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between brake switch terminal A and battery positive terminal
• Short to GND in wiring harness between brake switch terminal A and battery positive terminal
• Open circuit in wiring harness between brake switch terminal D and PCM terminal 1V
• Short to power supply in wiring harness between brake switch terminal D and PCM terminal 1V
• Short to GND in wiring harness between brake switch terminal D and PCM terminal 1V
• 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 the FREEZE FRAME DATA on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related service 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 | INSPECT BRAKE SWITCH CONNECTOR FOR POOR CONNECTION • Turn the ignition switch 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 terminal, then go to Step 10.
No | Go to the next step.

4

INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO GND
• Turn the ignition switch off.
• Inspect for continuity between the following circuits:

  - Brake switch terminal A (wiring harness-side) and body GND
  - Brake switch terminal D (wiring harness-side) and body GND

• Is there continuity?

Yes

Repair or replace the wiring harness for a possible short to GND, then go to Step 10.

No | Go to the next step.
5 | INSPECT BRAKE SWITCH CIRCUIT FOR SHORT TO POWER SUPPLY • Turn the ignition switch to the ON position (Engine off). • Measure the voltage between brake switch terminal D (wiring harness-side) and body GND. • Is the voltage B+? | Yes | Repair or replace harness for short to power supply, then go to Step 10.
No | Go to the next step.
6 | INSPECT BRAKE SWITCH • Inspect the brake switch. (See BRAKE SWITCH INSPECTION.) • Is there any malfunction? | Yes | Replace the brake switch, then go to Step 10. (See BRAKE PEDAL REMOVAL/INSTALLATION.)
No | Go to the next step.
7 | INSPECT PCM CONNECTOR FOR POOR CONNECTION • Turn the ignition switch off. • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction? | Yes | Repair or replace the terminal, then go to Step 10.
No | Go to the next step.
8 | INSPECT BRAKE SWITCH POWER CIRCUIT FOR OPEN CIRCUIT • Measure the voltage between brake switch terminal A (wiring harness-side) and body GND. • Is the voltage B+? | Yes | Go to the next step.
No | Repair or replace the wiring harness for a possible open circuit, then go to Step 10.
9 | INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT • Turn the ignition switch off. • Inspect for continuity between brake switch terminal D (wiring harness-side) and PCM terminal 1V (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 the next step.

10

VERIFY TROUBLESHOOTING OF DTC P0703 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• 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 should exceed 3.8 km/h {2.4 mph} per 0.1 s

• Is the PENDING CODE for this DTC present?

Yes

Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [ZJ, Z6].)

No | Go to the next step.
11 | VERIFY AFTER REPAIR PROCEDURE • Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [ZJ, Z6].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [ZJ, Z6].)
No | DTC troubleshooting completed.