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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P2503 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P2503 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 DRIVE CHAIN CONDITION 
  • Verify that drive belt auto tensioner indicator mark does not exceed limit.
  • Is drive belt normal?
 Yes Go to the next step.
No Replace and/or adjust drive chain, then go to Step 10.
4 INSPECT POOR CONNECTION OF PCM CONNECTOR 
  • Turn the ignition switch off.
  • Disconnect PCM connector.
  • Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.).
  • Is there any malfunction?
 Yes Repair the terminals, then go to Step 10.
No Go to the next step.
5 INSPECT POOR CONNECTION OF GENERATOR CONNECTOR 
  • Disconnect 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 10.
No Go to the next step.
6 INSPECT GENERATOR CONTROL CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between generator terminal D (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Repair or replace the wiring harness for short to ground, then go to Step 10.
No Go to the next step.
7 INSPECT GENERATOR OUTPUT VOLTAGE MONITOR CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between generator terminal P (wiring harness-side) and body ground.
  • Is there continuity?
 Yes Repair or replace the wiring harness for short to ground, then go to Step 10.
No Go to the next step.
8 INSPECT GENERATOR CONTROL CIRCUIT FOR OPEN 
  • Inspect for continuity between generator terminal D (wiring harness-side) and PCM terminal 2AI (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for open circuit, then go to Step 10.
9 INSPECT GENERATOR OUTPUT VOLTAGE MONITOR CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between generator terminal P (wiring harness-side) and PCM terminal 2AJ (wiring harness-side).
  • Is there continuity?
 Yes Repair or replace the generator, then go to the next step.
No Repair or replace the wiring harness for open circuit, then go to the next step.
10 VERIFY TROUBLESHOOTING OF DTC P2503 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.
11 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE  .)
No Troubleshooting completed.
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