2026-05-08

Car Computer (Remove and Replace)

Correction code 21153202 (HW3) 21153302 (HW4) FRT 0.96 0.84 NOTE: Unless otherwise explicitly stated in the procedure, the correction code and FRT listed above reflect all of the work required to perform this procedure, including the linked procedures. Do not stack correction codes unless explicitly told to do so. NOTE: See Flat Rate Times to learn more about FRTs and how they are created. NOTE: See Personal Protection to make sure you are wearing proper PPE when performing the procedure below. NOTE: See Ergonomic Precautions for safe and healthy working practices.

  • 2026-05-08: Removed the air purge step, as the cooling system vacuum refill is included in the Car Computer (Remove and Install) and not required to operate the air purge routine again.
  • 2025-03-13: Added 3rd party security credentials check.
  • 2024-12-17: Added instructions on Ethernet Diagnostics retrofit for Model S with HW3 car computer
  • 2024-10-17: Added instruction for car computer disposal.
  • 2024-09-06: Added owner authorization request and LV maintainer steps.

Replace Car Computer

  1. Connect a laptop with Toolbox to the vehicle. See Toolbox (Connect and Disconnect).
  2. For Third Party repairs only: Perform the Toolbox Owner Authorization Request.
    Informational PurposesAn informational icon, calling your attention
    Note
    If the repair was booked through Tesla Service, the customer has already given authorization. Go to the next step.
    1. Log in to https://toolbox.tesla.com/help/owner_authorization.
    2. On the left panel, click Owner Authorization Request, and then click Request Owner Authorization in the main panel.
    3. Complete and submit the form.
    4. Ask the vehicle owner to approve the authorization request that was sent to their email.
  3. Click on Dashboards > Car Computer Replacement and on the "Getting Started" page, click on Next Step.
  4. On the "Backup & Factory Reset" page, click Next Step and follow the prompts to perform a profile backup and factory reset on the car computer.
    Informational PurposesAn informational icon, calling your attention
    Note
    The car computer will reboot several times during this step.
  5. Once the "Replace" page appears, the car computer can be replaced. Use the instructions in the appropriate "Remove and Install" procedure to replace the car computer:
    Select the appropriate Car Computer (Remove and Install) procedure:
  6. Re-establish the Toolbox laptop connection, and in the "Replace" page, click Next Step.
  7. For Third Party repairs only: Enter the vehicle security professional login credentials that are required in order to proceed to the "Associate Car Computer" section.
    Informational PurposesAn informational icon, calling your attention
    Note
    Parts considered security and/or theft-relevant, or which may require special programming and/or setup, are only able to be configured by automotive professionals that are registered with a vehicle security accreditation organization, or by Tesla Service Technicians.
  8. Follow the prompts to transfer configurations and associate the replacement car computer. The car computer will reboot several times.
  9. When association is complete and the VIN is confirmed online, click Next Step to go to the "Update" page.
    Informational PurposesAn informational icon, calling your attention
    Note
    If necessary, Reconnect the Toolbox connection.
  10. Click Start Part Replacement OTA to deploy a software update to the vehicle.
    Informational PurposesAn informational icon, calling your attention
    Note
    If necessary, Reconnect the Toolbox connection.
  11. Re-install software via UI
    Informational PurposesAn informational icon, calling your attention
    Note
    Via Controls > Service Mode > Software Reinstall
  12. In Toolbox, click Next Page to go to the "Restore" page, and then follow the prompts to restore the vehicle profile.
  13. If the car computer HW3 or HW4 andis equipped with a physical SIM card, perform the routine below; otherwise skip this step.
    1. Perform the following routine using Service Mode or Toolbox (see 0005 - Service Modes): PROC_ICE_X_ENABLE-DISABLE-SIM-CARDvia Service Mode Plus:Infotainment ➜ Connectivity ➜ Toggle SIMvia Toolbox:(link)
  14. Disconnect the laptop from the vehicle.
  15. Install the remaining components that were removed for access.
    Select the appropriate Car Computer (Remove and Install) procedure:
  16. Make sure to properly dispose of the old car computer. Follow the instructions in Car Computer (Dispose) and add correction code 21151007 as a separate activity to the Service Visit.

Ethernet Diagnostics Retrofit (HW3 Model S only)

Parts required for this procedure:
  • 1783315-00-A MCU,RJ45,JUMPER
  • 1681904-00-A ETHERNET DIAGNOSTIC - RJ45 MODULE
If the vehicle requires an Ethernet diagnostics retrofit, perform the following steps when connecting the electrical harnesses to the replacement car computer. See Service Manual procedure Car Computer (HW3) (Remove and Install).
  1. Connect all electrical harnesses to the car computer as instructed in the Service Manual, except for X455 and the gaming MCU connector.
    Figure 1. Connector X455 at RH side of car computer
    Figure 2. Gaming MCU connector at LH side of car computer
  2. Connect the X455 electrical harness to the Ethernet diagnostics jumper box, and then engage the connector lock.
    Figure 3. Ethernet diagnostics jumper harness connections
  3. Install the clip that attaches the Ethernet diagnostics jumper box to the RH body harness bracket.
  4. Connect the Ethernet diagnostics car computer connector (Figure 3, orange) to car computer connection X455, and then engage the locking tab.
  5. Route the diagnostic connector (Figure 3, green) behind the upper car computer mounting bracket.
  6. Insert a flexible pickup tool down the inner RH side of the center console, and pull the diagnostic connector up to the service panel.
  7. If not already present, install the Ethernet diagnostic RJ45 module on the service panel.
  8. Connect the diagnostic connector to the Ethernet diagnostic RJ45 module, and then engage the locking tab (Figure 29).
  9. Use electrical tape to attach the Ethernet diagnostics jumper harness to the IP harness.
  10. Connect the electrical harness to the car computer gaming MCU connector.
    Informational PurposesAn informational icon, calling your attention
    Note
    Make sure the locking tab engages the connector port and locks the connector in place.
  11. Go to step #NHL_FFN_SDC__GUID-CDD509ED-B7B9-473F-B98D-5DF6769FCD7B of the “Replace Car Computer” section and complete the remainder of the procedure.