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                        | Last Modified: 08-21-2023 | 6.11:8.1.0 | Doc ID: RM100000001B2OH |  
                        | Model Year Start: 2019 | Model: Avalon HV | Prod Date Range: [04/2018 -                    
                                       ] |  
                        | Title: THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): B279C95; Engine Immobiliser System Incorrect Assembly; 2019 - 2022 MY Avalon HV [04/2018 -        ] |  
                     
                        
                           | DTC | B279C95 | Engine Immobiliser System Incorrect Assembly |  DESCRIPTIONIf a hybrid vehicle control ECU that is incompatible with the immobiliser function is installed, the hybrid vehicle control ECU will store this DTC. 
                     
                        
                        
                        
                        
                        
                     
                     
                        
                           | DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Note |  
                           | B279C95 | Engine Immobiliser System Incorrect Assembly | A hybrid vehicle control ECU that is incompatible with the immobiliser function is installed. (1-trip detection logic*) | Hybrid vehicle control ECU | - |  
                     
                        
*: Only detected while a malfunction is present.
 Vehicle Condition and Fail-safe Function when Malfunction Detected
                     
                        
                        
                     
                     
                        
                           | Vehicle Condition when Malfunction Detected | Fail-safe Function when Malfunction Detected |  
                           | Hybrid control system cannot be started | - |  Related Data List and Active Test
                     
                        
                        
                     
                     
                        
                           | DTC No. | Data List and Active Test |  
                           | B279C95 | - |  CAUTION / NOTICE / HINT
                     NOTICE: 
                        
When using the Techstream with the power switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
The smart key system (for Start Function, HV Model) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the smart key system (for Start Function, HV Model) after confirming that the communication systems are functioning properly.
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                                       ![2019 - 2022 MY Avalon HV [04/2018 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif) 
Before replacing the hybrid vehicle control ECU, refer to Registration.
Click here
                                 
                                    
                                       ![2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION](/t3Portal/stylegraphics/info.gif)  ![2021 - 2022 MY Avalon HV [08/2020 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION](/t3Portal/stylegraphics/info.gif) 
After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".
 PROCEDURE
                     
                        
                           | 1.  | REPLACE HYBRID VEHICLE CONTROL ECU |  (a) Temporarily replace the hybrid vehicle control ECU with a new one. Click here
                        
                           
                              ![2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL](/t3Portal/stylegraphics/info.gif)  ![2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID VEHICLE CONTROL ECU: REMOVAL](/t3Portal/stylegraphics/info.gif)  
                     
                        
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