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Diagnostic Trouble Code Chart

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.
  1. TRANSPONDER KEY ECU DIAGNOSTIC TROUBLE CODE CHART 
    TRANSPONDER KEY ECU ASSEMBLY

    DTC Code Detection Item Trouble Area See
    B2780 Push Switch / Key Unlock Warning Switch Malfunction 1. Un-lock warning switch assembly
    2. Wire harness
    3. Transponder key ECU assembly
    Refer to DTC B2780: Push Switch / Key Unlock Warning Switch Malfunction
    B2784 Antenna Coil Open / Short 1. Wire harness
    2. Transponder key amplifier
    3. Transponder key ECU assembly
    Refer to DTC B2784: Antenna Coil Open / Short
    B2793 Transponder Chip Malfunction Key Refer to DTC B2793: Transponder Chip Malfunction
    B2794 Unmatched Encryption Code Key Refer to DTC B2794: Unmatched Encryption Code
    B2795 Unmatched Key Code Key Refer to DTC B2795: Unmatched Key Code
    B2796 No Communication in Immobilizer System 1. Key
    2. Transponder key amplifier
    3. Wire harness
    4. Transponder key ECU assembly
    Refer to DTC B2796: No Communication in Immobilizer System; DTC B2798: Communication Malfunction No. 2
    B2797 Communication Malfunction No. 1 1. Key
    2. Wire harness
    3. Transponder key amplifier
    4. Transponder key ECU assembly
    Refer to DTC B2797: Communication Malfunction No. 1
    B2798 Communication Malfunction No. 2 Key Refer to DTC B2796: No Communication in Immobilizer System; DTC B2798: Communication Malfunction No. 2
  2. ECM DIAGNOSTIC TROUBLE CODE CHART 
    NOTE:

    The DTCs for the engine immobilizer system are specified above. If other codes are output, check the DTC chart for the SFI system.

    ECM

    DTC Code Detection Item Trouble Area See
    B2799 Engine Immobilizer System Malfunction 1. Wire harness
    2. ECM
    3. Transponder key ECU assembly
    Refer to DTC B2799: Engine Immobilizer System Malfunction
    B279A Theft Deterrent System Communication Line High Fixation 1. Wire harness
    2. Transponder key ECU assembly
    3. ECM
    Refer to DTC B279A: Theft Deterrent System Communication Line High Fixation
    B279C Theft Deterrent System Presence Detection ECM Refer to DTC B279C: Theft Deterrent System Presence Detection