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Home >> Mazda >> 2003 >> MPV ES >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1603: Code Word Is Not Registered In Pcm >> Diagnostic Procedures
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Diagnostic Procedures

CAUTION: DO NOT crank engine before replacement PCM is programed to immobilizer system or PCM will be severely damaged. If test procedures require replacement of PCM on a vehicle equipped with immobilizer system, vehicle must be sent to authorized Mazda dealer to have replacement PCM programed.
  1. Check for service bulletins and on-line information. Repair as necessary. After repair, go to next step.
  2. Verify DTC P1603 Detected Again -  Using scan tool, clear all DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Turn ignition off. Start engine. If DTC P1603 is present, perform code word reprogram procedure. See appropriate IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT. If DTC P1603 is not present, go to next step.
  3. Verify Trouble Shooting Of DTC P1603 Completed -  Using scan tool, clear all DTCs. Turn ignition off. Start engine. Recheck DTCs. If same DTC is present, replace PCM. Perform immobilizer system reprogram procedure. See appropriate IMMOBILIZER SYSTEMS article in ACCESSORIES & EQUIPMENT. After repair, go to next step. If same DTC is not present, go to next step.
  4. Verify After Repair Procedure -  Using scan tool, perform after repair procedure. See AFTER REPAIR PROCEDURE . If DTC is not present, testing is complete. If any DTC is present, go to appropriate test for diagnosis and repair.
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