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Home >> Mazda >> 2006 >> MX-5 Miata Base >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P0550 >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0550 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 PSP SWITCH CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect PSP 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 7.
No Go to the next step.
4 INSPECT PSP SWITCH  Yes Go to the next step.
No Replace PSP switch, then go to Step 7.
5 INSPECT PSP SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • Disconnect PCM connector.
  • Inspect continuity between PSP switch terminal (harness-side) A and body ground.
  • Is there continuity?
 Yes Repair or replace harness for short to ground, then go to Step 7.
No Go to the next step.
6 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn ignition switch to OFF
  • Disconnect PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair terminal, then go to Step 7.
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0550 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Start engine.
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Drive vehicle above 60 km/h {37.3 mph}  for 1 min. 
  • Verify that ECT PID above 60°C {140°F}  using the WDS or equivalent.
  • Is PENDING CODE for this DTC present?
 Yes Replace 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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