Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

DTC P0703 [BP, BP WITH TC] 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.
1		No	Record FREEZE FRAME DATA on repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Check for related Service Bulletins and/or online repair information availability. Is any related repair information available?	Yes	Perform repair or diagnostic according to the available repair information. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR SHORT TO POWER Measure voltage between brake switch connector terminal B and body GND. Is voltage B+ ?	Yes	Repair or replace harness for short to power, then go to Step 9.
3		No	Go to Step 9.
4	INSPECT BRAKE SWITCH CONNECTOR FOR POOR CONNECTION Turn ignition switch to OFF. Disconnect brake switch connector. Check for poor connection (damaged, pulled-out terminals, corrosion, etc.). Is there any malfunction?	Yes	Repair or replace the terminal, then go to Step 9.
4		No	Go to the next step.
5	INSPECT BRAKE SWITCH POWER CIRCUIT FOR OPEN CIRCUIT Measure voltage between brake switch connector terminal A and body GND. Is voltage B+ ?	Yes	Go to the next step.
5		No	Repair or replace brake switch power circuit for open circuit, then go to Step 9.
6	INSPECT POOR CONNECTION OF PCM CONNECTOR Turn ignition switch to OFF. Disconnect PCM connector. Check for poor connection (damaged, pulled-out terminals, corrosion, etc.). Is there any malfunction?	Yes	Repair terminal, then go to Step 9.
6		No	Go to the next step.
7	INSPECT BRAKE SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT Connect brake switch connector. Turn ignition switch to ON. Depress brake pedal and measure voltage between PCM terminal 4B (harness-side) and body GND. Is voltage B+ ?	Yes	Go to the next step.
7		No	Repair or replace harness for open circuit, then go to Step 9.
8	INSPECT BRAKE SWITCH Inspect brake switch. (See BRAKE SWITCH INSPECTION ) Is it normal?	Yes	Go to the next step.
8		No	Replace brake switch, then go to the next step.
9	VERIFY TROUBLESHOOTING OF DTC P0703 COMPLETED Make sure to connect all disconnected connectors. Clear the DTC from the PCM memory using NGS tester. Drive vehicle 30 km/h {18.6 mph} or more. Depress and release brake pedal above 10 times during drive vehicle. Is same DTC present?	Yes	Replace PCM, then go to the next step.
9		No	Go to the next step.
10	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE ". (See AFTER REPAIR PROCEDURE ) Is any DTC present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE )
10		No	Troubleshooting completed.