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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P2504 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2504 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 POOR CONNECTION OF GENERATOR CONNECTOR 
  • Turn the ignition switch off.
  • Disconnect the generator connector.
  • Inspect for poor connection (damaged/pulled-out terminals, corrosion, etc.).
  • Is there any malfunction?
 Yes Repair or replace the terminals, then go to Step 8.
No Go to the next step.
4 CLASSIFY GENERATOR MALFUNCTION OR OTHER MALFUNCTION 
  • Turn the ignition switch to the ON (Engine off).
  • Measure the voltage between generator terminal D (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No There is a malfunction at the generator. Go to Step 7.
5 INSPECT POOR CONNECTION OF PCM CONNECTOR 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (damaged/pulled-out terminals, corrosion, etc.).
  • Is there any malfunction?
 Yes Repair or replace pins, then go to Step 8.
No Go to the next step.
6 INSPECT GENERATOR CONTROL CIRCUIT FOR SHORT TO POWER 
  • Turn the ignition switch to the ON (engine off).
  • Measure the voltage between generator terminal D (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the wiring harness for short to power supply, then go to Step 8.
No Go to Step 8.
7 INSPECT GENERATOR CONTROL TERMINAL FOR SHORT TO POWER 
  • Measure the voltage between generator terminal D (part-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the generator, then go to the next step.
No Go to the next step.
8 VERIFY TROUBLESHOOTING OF DTC P2504 COMPLETED 
  • Make sure to reconnect all connectors.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine, or perform the KOER self-test with WDS or equivalent.

    (See KOEO/KOER SELF TEST  .)

  • 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 Troubleshooting completed.
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