P1610 – Immobilizer System Malfunction (Toyota)
Description
The ECM detected a malfunction in the immobilizer system, preventing proper key authentication and engine start.
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View Recommended ScannersSymptoms
- No start condition
- Security light flashing
- Key not recognized
- Intermittent start issues
- Check engine light on
Causes
- Faulty key transponder
- Immobilizer antenna failure
- Wiring issues
- Weak battery
- ECM–immobilizer communication error
Diagnosis
- Check key function
- Test immobilizer antenna
- Inspect wiring
- Check battery voltage
- Scan immobilizer system
Repair
- Replace key
- Repair wiring
- Replace antenna coil
- Reprogram immobilizer
- Replace ECM if needed
