Diagnostic procedure

2010 Mazda 5 Sport, 2.3 L, StandardSECTION Diagnostic procedure
WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0125 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 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 VERIFY CURRENT INPUT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT? 
  • Connect the WDS or equivalent to the DLC-2.
  • Start the engine and warm it up completely.
  • Access the ECT PID.
  • Is the ECT PID more than 70 °C {158 °F}  ?
Yes Intermittent concern exists.
Perform the "INTERMITTENT CONCERNS TROUBLESHOOTING".
(See INTERMITTENT CONCERN TROUBLESHOOTING .)
No Go to the next step.
4 INSPECT ECT SENSOR  Yes Replace the ECT sensor, then go to Step 6.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
5 INSPECT MAF SENSOR  Yes Replace the MAF/IAT sensor, then go to the next step.
(See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
6 VERIFY TROUBLESHOOTING OF DTC P0125 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Access the ECT PID.
  • Wait until the ECT PID less than 20 °C {68 °F}. 
  • Start the engine and warm it up completely.
  • Is the PENDING CODE same as the DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
7 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.