Heated Seat Module

Remove and replace the heated seat module, located under the seat cushion, to restore heated seat functionality.

Warnings

Tools required

Parts

• Heated seat control module × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Ensure seat heaters have been off for at least 30 minutes to prevent burns
3. Open hood and disconnect negative battery terminal using appropriate socket, wait 15 minutes for airbag system to discharge
4. Move affected seat to full-forward position for access to rear mounting bolts
5. Photograph seat wiring connections for reference during reassembly

Procedure

1. 1

   Access seat mounting bolts
   Locate the seat rail mounting bolts securing the seat to the floor - verify the exact count and positions against OEM documentation. The front bolts are typically accessible with the seat in the full-rearward position, and the rear bolts with the seat in the full-forward position — verify the exact access orientation against OEM documentation before proceeding, as seat rail geometry varies. Verify fastener type before proceeding - these may be standard Torx, external Torx (E-Torx), or hex-head bolts depending on application. Note: These fasteners should be confirmed against OEM documentation before beginning work, as the exact head type (Torx, hex, or E-Torx) for 2009 DB9 seat rails has not been verified. Note: The fastener type (hex, internal Torx, or E-Torx) should be verified against OEM documentation before selecting a socket. Note: The rear bolts are accessible with the seat in the full-forward position. Move the seat to the full-rearward position to access the front bolts.
2. 2

   Remove seat mounting bolts
   Remove all seat mounting bolts (verify exact count against OEM documentation) using the appropriate driver for the confirmed fastener head type (standard Torx, hex, or E-Torx). Support the seat as you remove the final bolt to prevent it from shifting. Keep bolts organized for reinstallation.
3. 3

   Tilt and disconnect seat
   Carefully tilt the seat backward to expose the wiring harness connections underneath. Locate the main seat harness connector, heated seat connector, and any additional connectors (occupancy sensor, seat adjustment motors). Disconnect all electrical connectors by pressing the release tabs - do not pull on wiring. Remove the seat from the vehicle with assistance if needed due to weight.
4. 4

   Access seat cushion underside
   Place the seat upside down on a clean, padded surface to protect the leather. Locate the seat cushion attachment points - typically hog rings or metal clips securing the upholstery to the seat frame around the perimeter.
5. 5

   Release seat cushion cover
   Carefully release the hog rings or clips on one side of the seat cushion to create sufficient access to the heated seat module. You do not need to fully remove the upholstery - only create enough opening to access the module mounting bolts and connector. Work carefully to avoid tearing the leather or damaging the heated element mat.
6. 6

   Locate heated seat module
   Identify the heated seat module, which is typically a rectangular electronic control unit mounted to the seat frame or cushion base. It will have a wiring harness connecting to the heated element mat and another harness leading to the seat connector. The module is secured with mounting fasteners or clips - verify count and type against OEM documentation before removal.
7. 7

   Disconnect module wiring
   Disconnect the electrical connectors from the heated seat module. There will typically be one connector from the vehicle harness and one or two connectors to the heating element mat. Note the connector orientations and routing before disconnection.
8. 8

   Remove module mounting bolts
   Remove the module mounting bolts (verify exact count against OEM documentation — typically 2) using the appropriate Torx driver. Support the module as you remove the final fastener. Remove the module from the seat assembly.
   Torque spec

   Module Mounting Bolts8 Nm (6 lb-ft)
9. 9

   Inspect heating element and wiring
   With the module removed, visually inspect the heating element mat for any signs of damage, burns, or breaks in the heating wires. Check all wiring for chafing, cuts, or melted insulation. If the heating element is damaged, it must also be replaced. Use a multimeter to check heating element resistance if needed - compare the reading against the OEM-specified resistance value for this element. Note: Use a multimeter to check heating element resistance if needed - compare the reading against the OEM specification for the 2009 DB9, as the correct resistance range has not been verified in this procedure. Note: Use a multimeter to check heating element resistance if needed - compare the measured value against the OEM specification for this element (resistance varies by design and should not be assumed).
10. 10

    Install new module
    Position the new heated seat module in the mounting location, ensuring proper orientation and that wiring harnesses can reach without tension. Install the module mounting bolts and torque to specification using a torque wrench.
    Torque spec

    Module Mounting Bolts8 Nm (6 lb-ft)
11. 11

    Connect module wiring
    Connect the electrical connectors to the new module - heating element connector(s) first, then the vehicle harness connector. Ensure all connectors are fully seated and locking tabs are engaged. Route wiring away from any sharp edges or moving components.
12. 12

    Secure seat cushion cover
    Reinstall the hog rings or clips to secure the seat cushion upholstery to the frame. Ensure the cushion is properly positioned and tensioned - the upholstery should be smooth without wrinkles or excessive slack.
13. 13

    Reinstall seat assembly
    Position the seat over the mounting locations in the vehicle. Connect all electrical connectors underneath the seat in the reverse order of removal - main harness connector, heated seat connector, and any additional connectors. Ensure no wiring is pinched or routed where it could be damaged.
14. 14

    Secure seat to floor
    Install all seat mounting bolts (verify exact count against OEM documentation) finger-tight first to ensure proper alignment. Torque the bolts in a cross pattern to the OEM specification for the 2009 DB9 seat rail mounting bolts (this value must be verified against factory documentation and is not provided here). Verify the seat is secure and does not rock or shift. Note: Torque the bolts to the OEM specification (verify exact value from Aston Martin service documentation — do not guess, as seat anchoring is safety-critical).
15. 15

    Reconnect battery and test
    Reconnect the negative battery terminal and torque to specification. Start the vehicle and test the heated seat functionality on all heat settings. Verify the seat heats evenly and the control switches operate correctly. Check for any warning lights on the instrument cluster.
    Torque spec

    Battery Terminal Bolts6 Nm (4 lb-ft)

Reassembly

1. Torque all fasteners to specification - do not overtighten seat mounting bolts as this can damage threaded inserts
2. Ensure all electrical connectors are fully seated with locking tabs engaged
3. Verify seat moves freely on rails without binding after reinstallation
4. Test heated seat operation on all settings before returning vehicle to service

Verification

• Turn ignition to ON position and activate heated seat controls - verify indicator lights illuminate on dash or seat switch
• Allow seat to heat for 5-10 minutes and verify even heating across entire cushion surface
• Test all heat level settings (low, medium, high if equipped) to confirm module controls temperature correctly
• Check for any fault codes in vehicle system using diagnostic scan tool
• Verify no warning lights related to seat systems remain illuminated
• Confirm seat adjustment functions remain operational after reassembly

Related trouble codes on this vehicle

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