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Home >> Mazda >> 2017 >> 5 GS, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control (3 Of 3) >> DTC P0703-00: Brake Switch Input Circuit Problem >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0703:00 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 REPAIR INFORMATION AVAILABILITY
  • 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 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 9.
No Go to the next step.
4 INSPECT BRAKE SWITCH NO. 1 POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • 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 STOP 10 A fuse.
  • If the fuse is blown:
  • Repair or replace the wiring harness for a possible short to ground.
  • Replace the fuse.
  • If the fuse is deteriorated:
  • Replace the fuse.
  • If the fuse is normal:
  • Repair or replace the wiring harness for a possible open circuit.

Go to Step 9.
5 INSPECT BRAKE SWITCH NO. 1 SIGNAL CIRCUIT FOR SHORT TO GROUND
  • 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:
  • Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:

Go to Step 9.
No Go to the next step.
6 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 9.
No Go to the next step.
7 INSPECT BRAKE SWITCH NO. 1 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the brake switch and PCM connectors are disconnected.
  • 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 9.
No Go to the next step.
8 INSPECT BRAKE SWITCH NO. 1 SIGNAL CIRCUIT FOR OPEN CIRCUIT
  • Verify that the brake switch and PCM connectors are disconnected.
  • 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 Replace the brake switch, then go to the next step.
(See BRAKE PEDAL REMOVAL/INSTALLATION .)
No Repair or replace the wiring harness for a possible open circuit, then go to the next step.
9 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 .)
  • 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. (See ON-BOARD DIAGNOSTIC TEST .)
  • 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 .)
Go to the next step.
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE
 Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
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