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Firmware Reinstall - Contactors Open

  1. Remove the rear underhood apron. See Underhood Apron - Rear (Remove and Replace) .
  2. Connect the LV maintainer to the vehicle. See LV Maintainer (Connect and Disconnect) .
  3. Connect a laptop with Toolbox 3 to the vehicle. See TOOLBOX 3 (CONNECT AND DISCONNECT) .
    NOTE: Locally connecting the vehicle to Toolbox 3 will automatically enable Service Mode Plus.
  4. In Toolbox, select the Actions/Autodiag  tab, and then search for "redeploy".
  5. Run  the appropriate routine and wait for the reinstallation to complete. Reinstallation status can be monitored on the vehicle touchscreen.
    • Service CAN Redeploy (UPDATE_CAN-REDEPLOY)  - A "partial" firmware reinstallation that reinstalls the currently installed firmware package to all module, ECU, and component replacements, with the exception of the car computer.
    • Service Redeploy (UPDATE_SERVICE-REDEPLOY)  - A "full" firmware reinstallation that reinstalls the currently installed firmware package to the car computer, and all module, ECU, and component replacements.
    NOTE: The LVBMS is inside the LV battery, and because the LV battery is disconnected during the reinstallation, the LVBMS is not discoverable, and therefore is considered missing. Consequently, the firmware reinstall is incomplete, and it fails with the status "late_failure". Additionally, alert "VCBATT_a476_LVBMSMIA" might be seen. This is all normal, and will be rectified in later steps.
  6. Disconnect the LV maintainer from the vehicle and reconnect LV power. See LV Maintainer (Connect and Disconnect) .
  7. In Toolbox, select the Actions/Autodiag  tab, and then search for "redeploy".
  8. Select the same routine that was used in step  5.
  9. Click Run  , and wait for the reinstallation to complete. Reinstallation status can be monitored on the vehicle touchscreen.
    NOTE: During this second reinstall, the LV battery is connected and the LVBMS is discoverable, and so the reinstall should complete successfully. If it does not, or the status "late_failure" or alert "VCBATT_a476_LVBMSMIA" is displayed, investigate why.
  10. Verify that the firmware was successfully reinstalled and that the release notes are displayed.
    • If the reinstall failed, repeat from step  7.
    • If the reinstall succeeded, continue to the next step.
  11. On the vehicle touchscreen, touch CONTROLS (vehicle icon) > Service Mode > DIAGNOSTICS > Battery > LV Battery  , and then verify that the LV Battery SOC displayed is greater than 73%, and the HV battery BMS State displayed is "BMS_SUPPORT".
    • If the above conditions are not met, investigate the connection at the LV battery.
    • If the above conditions are met, and the firmware reinstall was performed as one step of another service procedure, return to that procedure.
    • If the above conditions are met, and the firmware reinstall was performed as a stand-alone procedure, continue to the next step.
  12. Disconnect the laptop from the vehicle. See TOOLBOX 3 (CONNECT AND DISCONNECT) .
  13. Disable Service Mode. See SERVICE MODE (ENABLE AND DISABLE) .
  14. Install the rear underhood apron. See Underhood Apron - Rear (Remove and Replace) .
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