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 P0123 [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 diagnosis 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	CHECK TP SENSOR CONNECTOR Turn the ignition switch off. Verify that the TP sensor connector is connected securely. Is connector okay?	Yes	Go to the next step.
3		No	Connect the connector securely, then go to Step 9.
4	INSPECT TP SENSOR CONNECTOR FOR POOR CONNECTION Disconnect TP sensor connector. Check for poor connection (damaged, pulled-out terminals, corrosion, etc.). Is there any malfunction?	Yes	Repair or replace suspected terminal, then go to Step 9.
4		No	Go to the next step.
5	CHECK TP SENSOR RESISTANCE Check resistance between following TP sensor terminals (part-side): Terminals A and B: Within 2.5-5 kilohms Terminals B and C: Within 0.2-1.1 kilohms Is resistance within specification?	Yes	Go to the next step.
5		No	Replace TP sensor, then go to Step 9.
6	VERIFY TP SENSOR GND CIRCUIT FOR OPEN CIRCUIT AT TP SENSOR CONNECTOR Check continuity between TP sensor terminal B (harness-side) and body GND. Is there continuity?	Yes	Go to Step 8.
6		No	Go to the next step.
7	CHECK PCM CONNECTOR Disconnect PCM connector. Check for poor connection at terminal 4L, 4V and 4O (damaged, pulled-out terminals, corrosion, etc.). Is there any malfunction?	Yes	Repair terminal, then go to Step 9.
7		No	Repair or replace harness for open circuit, then go to Step 9.
8	VERIFY TP SIGNAL CIRCUIT FOR SHORT TO CONSTANT VOLTAGE CIRCUIT Check continuity between TP sensor harness-side connector terminals A and C. Is there continuity?	Yes	Repair or replace suspected harness, then go to the next step.
8		No	Go to the next step.
9	VERIFY TROUBLESHOOTING OF DTC P0123 COMPLETED Make sure to connect all disconnected connectors. Start engine. Clear the DTC from the PCM memory using the WDS or equivalent. Depress and release accelerator pedal several times. 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.