LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3 With TC] >> DTC P2503 >> Diagnostic procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic procedure

DTC P2503 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has the 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 the 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 the drive chain auto tensioner indicator mark does not exceed limit.
  • Is the front drive chain normal?
 Yes Go to the next step.
No Replace the and/or adjust drive chain, then go to Step 10.
4 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • 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 the terminals, then go to Step 10.
No Go to the next step.
5 INSPECT GENERATOR CONNECTOR FOR POOR CONNECTION 
  • 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 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 a 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 a 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 1AD (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for an 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 1AB (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 an 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.
  • 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.
scientia non olet · About LEMON Manuals