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1997 TOYOTA 4RUNNER
3.0L V6•4WD•AUTOMATIC•gas
4 active safety recalls on this vehicle — view recalls
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Repairs0Labor1028Torque6708Fluid18DTC1806Battery2Maintenance0Recalls4
B0100high severityBody

Immobilizer System General Malfunction

on 1997 Toyota 4Runner 3.0L V6 · 4WD

What this code means

A general fault detected in the engine immobilizer system. The immobilizer prevents engine starting without a recognized key or transponder.

Symptoms

  • Engine cranks but will not start
  • Security/immobilizer warning light on
  • Key not recognized
  • Intermittent no-start condition

Common causes

  • Faulty key transponder
  • Immobilizer antenna ring failure
  • Immobilizer control module fault
  • Key not programmed to vehicle
  • Weak key battery

Diagnostic steps

  1. Try spare key
  2. Check immobilizer warning light pattern
  3. Scan immobilizer module for specific codes
  4. Test transponder ring antenna
  5. Verify key programming status

Repair notes

Try spare key first. Reprogram key to immobilizer if needed. Replace antenna ring or immobilizer module if faulty.

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Other Body codes on this vehicle

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