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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P2128 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2128 DIAGNOSTIC PROCEDURE TABLE

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 INSPECT APP SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the APP sensor 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 8.
No Go to the next step.
4 INSPECT APP SENSOR NO.2 SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between the following circuits:
    • APP sensor terminal B (wiring harness-side) and PCM terminal 1AV
    • APP sensor terminal C (wiring harness-side) and PCM terminal 1AP
  • Is the voltage B+  ?
Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 8.
No Go to the next step.
5 INSPECT APP SENSOR NO.2  Yes Replace the APP sensor, then go to Step 8.
(See ACCELERATOR PEDAL REMOVAL/INSTALLATION .)
No Go to the next step.
6 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 8.
No Go to the next step.
7 INSPECT APP SENSOR NO.2 GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch off.
  • Inspect for continuity between APP sensor terminal B (wiring harness-side) and PCM terminal 1AV (wiring harness-side).
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the wiring harness for a possible an open circuit, then go to the next step.
8 VERIFY TROUBLESHOOTING OF DTC P2128 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine.
  • Is the same DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.