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Home >> Mazda >> 2003 >> MX-5 Miata Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0605: Internal Control Module Read Only Memory Error >> Diagnostic Procedure
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Diagnostic Procedure

  1. Perform DTC Confirmation Procedure -  Turn ignition off. Connect scan tool to DLC-2. See Figure. Turn ignition on, engine off. Perform KOEO Self-Test. If same P0605 is present, replace PCM. For PCM removal and installation, see POWERTRAIN CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION article. After repair, go to next step. If no DTC is present, problem is intermittent. See INTERMITTENTS in TROUBLESHOOTING - NO CODES article.
  2. Verify After Repair Procedure -  Using scan tool, perform After Repair Procedure. See AFTER REPAIR PROCEDURE . If no other DTCs are present, testing is complete. If any other DTC is present, go to applicable test and repair.
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