P1611 – Immobilizer Incorrect Key (Toyota)
Description
The ECM detected an incorrect or unregistered key signal during the immobilizer authentication process.
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View Recommended ScannersSymptoms
- No start condition
- Security light flashing
- Key not accepted
- Intermittent start issues
- Immobilizer warning
Causes
- Wrong key used
- Unprogrammed key
- Weak key transponder
- Immobilizer antenna fault
- ECM recognition error
Diagnosis
- Verify correct key
- Test transponder signal
- Inspect antenna coil
- Check ECM communication
- Scan immobilizer system
Repair
- Use correct key
- Reprogram key
- Replace antenna coil
- Repair wiring
- Replace ECM if required
