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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P2502 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2502 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 BATTERY 
  • Turn the ignition switch off.
  • Inspect the battery.
  • Is the battery normal?
 Yes Go to the next step.
No Replace the battery, then go to Step 7.
4 INSPECT POOR INSTALLATION OF GENERATOR TERMINAL 
  • Turn the ignition switch off.
  • Inspect for looseness of generator terminal B installation nut.
  • Is nut loose?
 Yes Tighten generator terminal B installation nut, then go to Step 7.
No Go to the next step.
5 INSPECT POOR INSTALLATION OF BATTERY POSITIVE TERMINAL 
  • Inspect for looseness of battery positive terminal.
  • Is the terminal loose?
 Yes Connect the battery positive terminal correctly, then go to Step 7.
No Go to the next step.
6 INSPECT BATTERY CHARGING CIRCUIT 
  • Disconnect the generator terminal B.
  • Measure the voltage between generator terminal B (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness between generator terminal B and battery positive terminal, then go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P2502 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.
8 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE  .)
No Troubleshooting completed.
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