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1998 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1042Torque1610Fluid17DTC3334Battery2Maintenance0Recalls5
P0633high severityPowertrain

Immobilizer Key Not Programmed - ECM/PCM

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The immobilizer key data has not been programmed into the PCM. The engine may not start until the key is properly learned.

Symptoms

  • Engine no-start
  • Security/immobilizer light on
  • Check engine light on

Common causes

  • PCM replaced without key programming
  • Immobilizer key not learned
  • Faulty immobilizer module
  • Faulty PCM

Diagnostic steps

  1. Scan immobilizer and PCM for related codes
  2. Verify key programming status
  3. Program/relearn keys with proper tool
  4. Confirm engine starts and code clears
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Other Powertrain codes on this vehicle

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