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Problem Symptoms Table

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

HINT: 

If any malfunction still exists even after checking and confirming that all the circuits are normal, replace the ECU.

ENGINE IMMOBILIZER SYSTEM

Symptom Suspected Area See
Immobilizer is not set. (Engine starts with key codes other than the registered key code.) 1. Door courtesy switch circuit Refer to Door Courtesy Switch Circuit
2. Transponder key ECU assembly -
Engine does not start. 1. Key Refer to DATA LIST / ACTIVE TEST 
2. Key unlock warning switch circuit Refer to DTC B2780: Push Switch / Key Unlock Warning Switch Malfunction
3. Transponder key amplifier circuit Refer to DTC B2784: Antenna Coil Open / Short
4. Transponder key ECU assembly -
5. SFI system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Security indicator is always ON. 1. Security indicator light Refer to Security Indicator Light Circuit
2. Transponder key ECU assembly -
Security indicator is always ON. (Although code has been registered in the automatic registration mode, indicator does not go off.) 1. Transponder key amplifier circuit Refer to DTC B2784: Antenna Coil Open / Short
2. Transponder key ECU assembly -
Security indicator is OFF. 1. Security indicator light circuit Refer to Security Indicator Light Circuit
2. Transponder key ECU assembly -
Security indicator is abnormally blinking. Transponder key ECU assembly -
No code is output. 1. ECU power source circuit Refer to ECU Power Source Circuit
2. Diagnosis circuit Refer to Diagnosis Circuit
3. Transponder key ECU assembly -