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Home >> Mazda >> 2001 >> MX-5 Miata Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1604: Code Word Unregistered In Pcm >> Condition
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DTC P1604: Code Word Unregistered In Pcm: Condition

DTC is set when immobilizer unit code is not registered in Powertrain Control Module (PCM). Possible causes are: