P1615 – Immobilizer Wrong Signal (Toyota)

Description

The ECM detected an incorrect immobilizer signal during key authentication, preventing engine start.

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Symptoms

  • No start condition
  • Security light flashing
  • Key not accepted
  • Intermittent start issues
  • Immobilizer warning

Causes

  • Weak key transponder
  • Signal interference
  • Faulty antenna coil
  • Wiring issues
  • Immobilizer ECU error

Diagnosis

  • Test key transponder
  • Inspect antenna coil
  • Check wiring
  • Scan immobilizer system
  • Verify ECM communication

Repair

  • Reprogram key
  • Replace antenna coil
  • Repair wiring
  • Replace immobilizer ECU

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