2026-03-26

Cover - Ancillary Bay (Remove and Install)

Correction code 16101001 0.96 NOTE: Unless otherwise explicitly stated in the procedure, the above correction code and FRT 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 wearing proper PPE when performing the below procedure. NOTE: See Ergonomic Precautions for safe and healthy working practices.

  • 2025-10-17: Removed HVC rework steps. Specified that all Model 3 vehicles must use an ancillary cover with volcano brackets.
  • 2025-10-13: Added warning at step to remove/install the ancillary bay cover to do this while standing outside the vehicle.
  • 2024-04-04: Added information on installing and removing ancillary bay kit insulators.
  • 2023-06-09: Corrected paint pen colors.
  • 2023-05-22: Added caution for correct positive DC cable connection.
Equipment:
  • 1127845-00-A Asy, Service Cover, Penthouse, Model 3
  • 1059330-00-B Skt, 1/4in Dr, 5-Lobe Torx Plus External
  • 1076971-02-A Wrench, Torque + Angle, 1/4" Dr
  • 1108272-00-B Cap, Logic Conn, Inv, 3DU
Warning IconA warning icon, calling your attention to a possibly risky situation
Warning
Remove all jewelry (watches, bracelets, rings, necklaces, earrings, ID tags, piercings, etc.) from your person, and all objects (keys, coins, pens, pencils, tools, fasteners, etc.) from your pockets before performing any procedure that exposes you to high voltage.
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Warning
If corrective eyewear is necessary to safely perform any procedure, make sure that the eyewear is securely restrained to the head and cannot fall off.
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Warning
Only technicians who have completed all required certification courses are permitted to perform this procedure. Tesla recommends third party service provider technicians undergo equivalent training before performing this procedure. For more information on Tesla Technician requirements, or descriptions of the subject matter for third parties, see HV Certification Requirements. Proper personal protective equipment (PPE) and insulating HV gloves with a minimum rating of class 0 (1000V) must be worn at all times a high voltage cable, busbar, or fitting is handled. Refer to Tech Note TN-15-92-003, High Voltage Awareness Care Points for additional safety information.
Warning IconA warning icon, calling your attention to a possibly risky situation
Warning
When servicing the ancillary bay cover and components in or around the ancillary bay, there is a possibility of encountering metal flashing on the inner edge of the vehicle single-piece rear casting. These sharp protrusions are a cut hazard, and proper PPE should be worn if there is a chance of contacting the flashing unprotected. If not already wearing leather over gloves, then at least wear cut-resistant gloves when the flashing is present.

Torque Specifications

Table 1. Torque Specifications: Cover - Ancillary Bay (Remove and Install)
Description Torque Value Recommended Tools Reuse/Replace Notes
Bolts that attach the ancillary bay rails to the body and ancillary bay cover
24 Nm (17.7 lbs-ft)
  • 15 mm socket
  • Torx T40 socket
Reuse
Nut that attaches the positive 12V output cable to the DCDC passthrough
9 Nm (6.6 lbs-ft)
  • 13 mm 12-point deep socket
Replace 1523698-00-A
Bolts that attach the ancillary bay cover to the high voltage controller
5 Nm (3.7 lbs-ft) +30 deg
  • External Torx E10
Reuse
Bolt attaches the ancillary bay cover to the HV battery
10.5 Nm (7.7 lbs-ft)
  • External Torx E10 5-Lobe
Reuse

Remove

  1. Remove the 2nd row lower seat cushion. Seat Cushion - Lower - 2nd Row (Remove and Replace).
  2. Disconnect 12V power. See 12V/LV Power (Disconnect and Connect).
  3. Remove the 2nd row ancillary bay 12V cap.
  4. Perform Vehicle HV Disablement Procedure. See Vehicle HV Disablement Procedure.
  5. Disconnect the electrical harness from the high voltage controller connector.
    Informational PurposesAn informational icon, calling your attention
    Note
    The HV battery positive contactor and negative contactor open with a clunk sound.
  6. Install the logic connector cap onto the high voltage controller connector to prevent mistaken reconnection and protect the connector.
  7. Remove the 2nd row ancillary bay high voltage cap.
  8. Remove the bolts that attach the ancillary bay rails to the body and ancillary bay cover, and then remove the rails from the vehicle.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • 15 mm socket
    • Torx T40 socket
  9. Remove the LH 2nd row buckle. See Buckle - 2nd Row - LH (Remove and Replace).
  10. Remove the center 2nd row buckle. See Buckle - 2nd Row - Center (Remove and Replace).
  11. If the leather over gloves have been removed, inspect the inner edge of the vehicle single-piece rear casting for flashing. If flashing is present, put on cut-resistant gloves.
  12. Release the cover on the positive 12V output cable, at the DCDC passthrough.
  13. Remove the nut that attaches the positive 12V output cable to the DCDC passthrough, and then remove the cable from the passthrough.
    Informational PurposesAn informational icon, calling your attention
    Note
    Inspect the condition of the rubber boot at the end of the output cable, and replace the boot if it is melted or damaged.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • 13 mm 12-point deep socket
  14. Remove the bolts that attach the high voltage controller internally to the ancillary bay cover.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • External Torx E10
    Figure 1. 5-Bolt HVC Ancillary Bay Cover
    Figure 2. 4-Bolt HVC Ancillary Bay Cover
    Figure 3. 3-Bolt HVC Ancillary Bay Cover
  15. Remove the bolts that attach the ancillary bay cover to the HV battery, and remove the ancillary bay cover from the vehicle.
    Warning IconA warning icon, calling your attention to a possibly risky situation
    Warning
    Remove the ancillary bay cover from the vehicle while standing outside the vehicle to reduce the risk of falling into the open HV battery.
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    Use an External Torx E10 5-Lobe socket that is not magnetized. Sockets with magnets will not fully grip and can possibly strip the bolt head.
    Informational PurposesAn informational icon, calling your attention
    Note
    Different ancillary bay cover revisions have 28, 18, or 16 bolts.
    Informational PurposesAn informational icon, calling your attention
    Note
    The bolts are captive to the ancillary bay cover.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • External Torx E10 5-Lobe
  16. Visually inspect the interior of the ancillary bay for insulators on the high voltage components.
    • If any of the insulators are missing, install the missing insulators. See Insulators - HV Battery (Install and Remove).
    • If all of the insulators are installed, continue to the procedure that required the ancillary bay cover to be removed.

Install

  1. Use an IPA wipe to clean any residue from the high voltage controller mounting bolt holes and both the inside and outside of the ancillary bay cover at the bolt holes.
  2. Use IPA wipes to clean the ancillary bay cover gasket surface, and the mating surface of the HV battery.
  3. If the aluminum tape retrofit patch is missing or damaged, remove the patch (if present), clean the area with an IPA wipe, apply another patch of aluminum tape, and wet out the patch with a silicone roller to set the adhesive.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • 3M 425 Aluminum Foil Tape - 0601363
    Figure 4. 5-Bolt to 4-Bolt Patch 50mm x 50mm
    Figure 5. 4-Bolt to 3-Bolt Patch 30mm x 30mm
  4. Inspect the inner edge of the vehicle single-piece rear casting for metal flashing. If flashing is present and the leather over gloves have been removed, put on cut-resistant gloves.
  5. Inspect ancillary bay walls for damage.
    Informational PurposesAn informational icon, calling your attention
    Note
    Any dent or depression in the seal that causes it to not be flat will result in a leak, and cannot be reused. Any paint that comes off the ancillary bay wall, whether or not it sticks to the seal, will require enclosure leak test when reassembled.
  6. Inspect the ancillary bay cover seal to confirm it has no visual damage.
    Informational PurposesAn informational icon, calling your attention
    Note
    Image up close for clarity. Delaminated and torn seals cannot be reused.
  7. Install the ancillary bay cover to the HV battery.
    Warning IconA warning icon, calling your attention to a possibly risky situation
    Warning
    Install the ancillary bay cover to the HV battery while standing outside the vehicle to reduce the risk of falling into the open HV battery.
  8. Install the logic connector cap onto the high voltage controller connector.
  9. Install the ancillary bay cover bolts in the sequence shown, and mark each with an orange paint pen as they are torqued.
    10.5 Nm (7.7 lbs-ft)
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    Use an External Torx E10 5-Lobe socket that is not magnetized. Sockets with magnets will not fully grip and can possibly strip the bolt head.
    Informational PurposesAn informational icon, calling your attention
    Note
    Different ancillary bay cover revisions have 28, 18, or 16 bolts.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • External Torx E10 5-Lobe
    Figure 6. 28-Bolt Ancillary Bay Cover Torque Sequence
    Figure 7. 18-Bolt Ancillary Bay Cover Torque Sequence
    Figure 8. 16-Bolt Ancillary Bay Cover Torque Sequence
  10. Remove the HV insulating gloves.
  11. Install the high voltage controller to ancillary bay cover bolts in the sequence shown, and mark each bolt with an orange paint pen as they are torqued.
    5 Nm (3.7 lbs-ft) +30 deg
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    Insufficient torque of bolts 1 and 2 opens the high voltage interlock loop circuit.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • External Torx E10
    Figure 9. 5-Bolt HVC Ancillary Bay Cover
    Figure 10. 4-Bolt HVC Ancillary Bay Cover
    Figure 11. 3-Bolt HVC Ancillary Bay Cover
  12. Connect the positive 12V output cable to the DCDC passthrough, install a new nut to attach the cable, and mark the nut with a pink/violet paint pen after torque.
    9 Nm (6.6 lbs-ft)
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    Make sure that the rubber boot is not trapped under the cable lug or pinched between the cable lug and nut.
    Warning IconA warning icon, calling your attention to a possibly risky situation
    CAUTION
    Make sure the positive output cable is positioned properly and in the right direction against the plastic anti-rotation edge on the DCDC passthrough.
    Informational PurposesAn informational icon, calling your attention
    Note
    Mark the fastener with a paint pen after torquing.
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • 13 mm 12-point deep socket
  13. Install the positive 12V output cover.
  14. Install the bolts that attach the rails to the ancillary bay cover and body.
    24 Nm (17.7 lbs-ft)
    Informational PurposesAn informational icon, calling your attention
    TIp
    Use of the following tool(s) is recommended:
    • 15 mm socket
    • Torx T40 socket
  15. Install the center 2nd row buckle. See Buckle - 2nd Row - Center (Remove and Replace).
  16. This video shows how to properly stack the 2nd row LH seat buckle onto the 2nd row center seat belt anchor:
  17. Set the 2nd row center seat belt anchor onto the 2nd row LH inner ancillary bay rail, with the belt to the RH side.
  18. Make sure that the belt is not twisted, and lays flat against the 2nd row seatback.
  19. Set the guide pin of the 2nd row LH seat buckle bracket into the hole of the 2nd row LH inner ancillary bay rail, and pivot the bracket down onto the anchor, aligning the guide pin to the slot in the anchor.
  20. Install a new bolt to attach the seat buckle bracket, the seat belt anchor, and the inner ancillary bay rail to the body.
    40 Nm (29.5 lbs-ft)
  21. Verify the stacking.
    Callout Description
    1 LH 2nd Row Buckle on Top
    2 Center 2nd Row Seatbelt Anchor in the Middle
    3 LH Inner Ancillary Bay Rail at the Bottom
  22. Install the plastic bracket that attaches the female side of the electrical connector to the body studs.
  23. Connect the electrical harness to the LH rear seat belt buckle connector.
  24. Install the LH 2nd row buckle. See Buckle - 2nd Row - LH (Remove and Replace).
  25. Install the 2nd row ancillary bay high voltage cap.
  26. Remove the logic connector cap from the high voltage controller connector.
  27. Connect the electrical harness to the high voltage controller connector.
  28. Install the 2nd row ancillary bay 12V cap.
  29. If damage was found on the ancillary bay cover gasket or the HV battery mating surface, or if the aluminum tape retrofit patch was replaced, or if another procedure instructed to perform an ancillary bay air leak test, do that now. See Ancillary Bay Air Leak Test.
  30. Install the 2nd row lower seat cushion. See Seat Cushion - Lower - 2nd Row (Remove and Replace).
  31. Connect 12V power. See 12V/LV Power (Disconnect and Connect).