B0105moderate severityBody

Immobilizer Key Count Exceeded

on 2003 Mazda Protege 1.6L I4 · FWD

What this code means

The maximum number of keys programmed to the immobilizer system has been exceeded or the key count is invalid.

Symptoms

  • Cannot program additional keys
  • Security light on
  • Key programming procedure fails

Common causes

  • All key slots used
  • Immobilizer memory error
  • Unauthorized key programming attempt detected
  • Module requires reset

Diagnostic steps

  1. Check number of keys programmed
  2. Attempt key count reset procedure
  3. Scan immobilizer for stored key data
  4. Verify key programming with dealer tool

Repair notes

Use dealer tool to reset key count and reprogram all valid keys.

Other Body codes on this vehicle

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