Heater Core

Complete heater core replacement requiring full dashboard removal, HVAC housing disassembly, and coolant system drain and refill.

Warnings

Tools required

Parts

• Heater core × 1 — Use OEM specification
• Heater core O-rings/seals × 1 — Typically included with heater core
• Dashboard fastener clips (assorted) × 1 — Order replacement set for broken clips
• Coolant (OAT 50/50 premix) × 1 — Use OEM specification

Fluids

• coolant — 10.5 qt

Preparation

1. Park vehicle on level surface and allow engine to cool completely (minimum 4 hours).
2. Disconnect negative battery terminal and wait 15 minutes for airbag system capacitor discharge.
3. Disconnect positive battery terminal and remove battery from vehicle for workspace clearance.
4. Have A/C system professionally evacuated and refrigerant recovered by certified technician.
5. Place coolant drain pan under driver-side front of vehicle.
6. Remove engine undertray to access coolant drain points.
7. Open coolant expansion tank cap slowly to release residual pressure.
8. Drain cooling system from radiator drain plug and lower coolant hoses at engine bay connections.
9. Collect and measure drained coolant for reference during refill.
10. Set up organized workspace with multiple parts trays and labeling system for fasteners by location.

Procedure

1. 1

   Remove front seats
   Slide each front seat fully rearward. Remove the Torx fasteners securing the seat rails to the floor at the front mounting points. Slide seats fully forward and remove the rear rail mounting fasteners. Disconnect electrical connectors under each seat (seat heating and power seat motors if equipped; the passenger seat may also have an occupancy/weight sensor connector). Carefully remove both seats from vehicle. Typically 4 fasteners per seat at rail mounting points.
2. 2

   Remove center console assembly
   Remove the gear selector surround trim by lifting from the rear edge. Disconnect the gear selector wiring harness. Remove Torx fasteners securing the center console front section (near footwell area). Remove Torx fasteners securing console rear section (behind armrest). Lift console upward while disconnecting any remaining electrical connectors for window switches, auxiliary power, and seat controls. Remove the entire console assembly as multiple sections, working front to rear.
3. 3

   Remove lower dashboard panels and footwell trim
   Remove the driver and passenger side lower dashboard trim panels by carefully prying at clip locations along the perimeter. Remove the knee bolsters on both sides by removing Torx fasteners at the upper and lower mounting points. Remove the A-pillar trim on both sides by pulling firmly from bottom to top to release retaining clips. Remove the door sill plates and footwell side trim panels on both sides to expose dashboard lower mounting points.
4. 4

   Remove steering wheel and column shrouds
   Turn steering wheel to access side fasteners. Remove Torx fasteners securing airbag module to steering wheel from side access holes. Carefully pull airbag module forward and disconnect yellow airbag connector and horn connector. Store airbag face-up in safe location away from work area. Mark steering wheel position relative to column shaft. Remove the steering wheel center bolt/nut. Verify the removal method against factory documentation; if a puller is required, use the correct steering wheel puller to remove the wheel from the splined shaft without damaging the clock spring. Remove Torx fasteners securing upper and lower column shrouds and remove both shroud pieces.
5. 5

   Disconnect steering column and remove
   Locate the steering column universal joint coupling at the base of the column (accessible from footwell). Mark the orientation of the coupling. Remove the pinch bolt securing the coupling to the steering rack input shaft. Remove Torx fasteners securing the steering column mounting bracket to the dashboard structure. Disconnect all electrical connectors from the column (multifunction switches, ignition, column adjustment motors if equipped). Carefully withdraw the steering column assembly from the dashboard.
6. 6

   Remove instrument cluster and surrounding trim
   Remove the upper dashboard trim piece above the instrument cluster by carefully prying at clip locations. Remove Torx fasteners securing the instrument cluster bezel. Remove Torx fasteners securing the instrument cluster to the dashboard housing. Pull cluster forward and disconnect the main harness connector and any additional connectors at the rear of the cluster. Remove cluster from vehicle. Remove side air vent assemblies by removing retaining fasteners and disconnecting any damper control connectors.
7. 7

   Disconnect dashboard main harness and controls
   Working from both driver and passenger sides, systematically disconnect all electrical connectors visible behind the dashboard face: HVAC control module, audio system, navigation screen, hazard switch, all air vent damper controls, ambient lighting modules, and passenger airbag connector. Photograph each connector before removal. Locate the main dashboard harness pass-through at the firewall and disconnect multi-pin connectors at this junction point. Label all connectors with tape and position.
8. 8

   Locate and remove dashboard mounting fasteners
   Working systematically, locate and remove all dashboard mounting fasteners. Check for fasteners at: upper dashboard edge near windshield (accessible after removing defroster grilles), both left and right A-pillar mounting points, center mounting points behind instrument cluster opening, lower mounting points in footwell areas on both sides, and mounting points where dashboard meets center tunnel. DB9 dashboards typically use a combination of Torx and E-Torx fasteners at mounting points. Remove all located fasteners and store by location.
   Torque spec

   Dashboard Screws3 Nm (2 lb-ft)
9. 9

   Remove dashboard assembly
   With all fasteners removed and all harnesses disconnected, have a second person assist in supporting the dashboard weight. Carefully pull the dashboard rearward while checking for any missed connections or fasteners. Lift the dashboard up and rearward to clear the steering column opening and A-pillar mounting points. Remove dashboard from vehicle through driver door opening. Place on padded surface to prevent damage to trim surfaces.
10. 10

    Disconnect heater hoses at firewall
    From the engine bay, locate the two heater hoses connecting to the heater core pipes at the firewall (verify side against the specific vehicle). Place absorbent towels around the connection area. Using hose clamp pliers, release the spring clamps or loosen screw-type clamps securing the heater hoses. Carefully pull hoses off the heater core pipes. Allow residual coolant to drain into a container. Cap or plug the hoses to prevent further coolant loss.
11. 11

    Remove HVAC housing assembly
    From inside the vehicle with dashboard removed, locate the HVAC housing unit mounted to the firewall. Disconnect any remaining electrical connectors to the blower motor, blend door actuators, and temperature sensors. Remove Torx fasteners securing the HVAC housing to the firewall and support brackets. The housing is secured at multiple points around its perimeter and may have additional fasteners at the transmission tunnel. Carefully maneuver the HVAC housing away from the firewall and remove from vehicle. This is a large, awkward component requiring careful handling.
12. 12

    Disassemble HVAC housing to access heater core
    Place the HVAC housing on a clean work surface. Remove Torx fasteners securing the housing halves together (typically located around the perimeter of the housing). Carefully separate the housing halves, noting the positions of any blend doors, seals, and actuator linkages. Locate the heater core mounting bracket and remove fasteners securing it. The heater core is typically retained by a metal bracket and foam seals. Carefully withdraw the old heater core from its cavity, noting the orientation of inlet/outlet pipes and any sealing arrangements.
    Torque spec

    Heater Core Mounting8 Nm (6 lb-ft)
13. 13

    Install new heater core and reassemble HVAC housing
    Inspect the heater core cavity in the HVAC housing for debris or damaged seals. Install new foam seals or O-rings onto the new heater core pipes as supplied with the replacement core. Carefully insert the new heater core into the housing cavity, ensuring the inlet/outlet pipes are oriented correctly to align with the firewall pass-through. Install the heater core mounting bracket and secure with fasteners torqued to specification. Inspect all blend door mechanisms and seals for damage before reassembly. Rejoin the HVAC housing halves, ensuring all seals are properly seated and blend door linkages are correctly positioned. Install and torque all housing fasteners to specification, working in a cross-pattern to ensure even clamping pressure.
    Torque spec

    Heater Core Mounting8 Nm (6 lb-ft)

    Dashboard Screws3 Nm (2 lb-ft)
14. 14

    Reinstall HVAC housing to vehicle
    With assistance, position the reassembled HVAC housing into the vehicle, aligning the heater core pipes with the firewall pass-through. Ensure the housing is properly seated against the firewall and mounting surfaces. Install all HVAC housing mounting fasteners and torque to specification. Reconnect all electrical connectors to the blower motor, blend door actuators, and temperature sensors in the reverse order of removal.
    Torque spec

    Dashboard Screws3 Nm (2 lb-ft)
15. 15

    Reconnect heater hoses at firewall
    From the engine bay, inspect the heater core pipe connections at the firewall. Ensure the O-rings or seals are properly seated. Slide the heater hoses onto the heater core pipes, ensuring they are fully seated. Install new hose clamps or reposition the original spring clamps to secure the hoses. If using screw-type clamps, torque to specification. Verify both connections are secure and properly positioned.
    Torque spec

    Heater Hose Clamps3 Nm (2 lb-ft)
16. 16

    Reinstall dashboard assembly
    With assistance, carefully position the dashboard assembly into the vehicle through the driver door opening. Align the dashboard with the A-pillar mounting points and steering column opening. Guide the dashboard into position, ensuring it seats properly against all mounting surfaces and the center tunnel. Install all dashboard mounting fasteners at the locations noted during removal: upper edge, A-pillars, center supports, footwell areas, and center tunnel mounts. Torque all fasteners to specification, working from the center outward to ensure even seating.
    Torque spec

    Dashboard Screws3 Nm (2 lb-ft)
17. 17

    Reconnect dashboard harness and controls
    Working systematically from your photographs and labels, reconnect all electrical connectors to the dashboard components: HVAC control module, audio system, navigation screen, hazard switch, all air vent damper controls, ambient lighting modules, and passenger airbag connector. Reconnect the main dashboard harness multi-pin connectors at the firewall pass-through. Verify all connectors are fully seated and locked. Route all harnesses as originally positioned to avoid pinch points or interference with moving parts.
18. 18

    Reinstall instrument cluster and trim
    Reconnect the main harness connector and any additional connectors to the rear of the instrument cluster. Position the cluster into the dashboard opening and secure with Torx fasteners. Install the instrument cluster bezel and secure with fasteners. Install the upper dashboard trim piece above the cluster, ensuring all clips engage properly. Reinstall side air vent assemblies with their retaining fasteners and reconnect damper control connectors.
19. 19

    Reinstall steering column and wheel
    Position the steering column assembly into the dashboard opening. Connect all electrical connectors to the column: multifunction switches, ignition, and column adjustment motors if equipped. Align the column mounting bracket with the dashboard structure and install mounting fasteners. Guide the column universal joint coupling onto the steering rack input shaft, aligning the marks made during removal. Install the pinch bolt and torque to specification. Position the steering wheel onto the splined shaft, aligning the marks made during removal. Install the steering wheel center nut and torque to specification. Reconnect the horn and yellow airbag connector to the airbag module. Install the airbag module to the steering wheel and secure with side fasteners. Install upper and lower column shrouds with Torx fasteners.
20. 20

    Reinstall footwell trim and lower panels
    Install the door sill plates and footwell side trim panels on both sides. Install the A-pillar trim on both sides, pressing firmly to engage all retaining clips from top to bottom. Install the knee bolsters on both sides with Torx fasteners at upper and lower mounting points. Install the driver and passenger side lower dashboard trim panels, pressing firmly at all clip locations around the perimeter to ensure secure engagement.
21. 21

    Reinstall center console assembly
    Position the center console assembly into the vehicle, working from front to rear. Connect all electrical connectors for window switches, auxiliary power, and seat controls. Install Torx fasteners securing the console rear section behind the armrest. Install Torx fasteners securing the console front section near the footwell area. Reconnect the gear selector wiring harness. Install the gear selector surround trim, pressing down at the rear edge to engage clips.
22. 22

    Reinstall front seats
    Position each front seat into the vehicle. Connect all electrical connectors under each seat: seat heating, occupancy sensor, and power seat motors. Slide seats fully forward and install the rear rail mounting fasteners. Slide seats fully rearward and install the front rail mounting fasteners. Verify seats slide smoothly and all electrical functions operate correctly.
23. 23

    Refill and bleed cooling system
    Install the engine undertray if previously removed. Verify all coolant drain points are closed and secure. Open the cooling system bleed valves if equipped (check for bleed screws at high points in the cooling system, typically near the thermostat housing or heater hose connections). Fill the coolant expansion tank with the Aston Martin specified coolant (verify correct chemistry/spec in factory documentation) mixed 50/50 to the MAX mark. Reconnect both battery terminals (positive first, then negative). Start the engine and allow it to warm to operating temperature with the heater set to maximum temperature. Monitor the coolant level and add coolant as needed during the bleeding process. Close bleed valves when coolant flows steadily without air bubbles. Allow the engine to cycle the thermostat fully open, then shut off and allow to cool. Recheck coolant level when cold and top off to the MAX mark. Note: Fill the coolant expansion tank with the Aston Martin-specified coolant (50/50 premix per factory specification) to the MAX mark.
    ⚠Engine and coolant will become extremely hot during bleeding process. Use caution when checking coolant level or closing bleed valves.
24. 24

    A/C system evacuation and recharge
    Have the A/C system professionally evacuated using a vacuum pump to remove all air and moisture (minimum 30 minutes vacuum hold). After successful vacuum test, recharge the system with the correct refrigerant type and charge quantity per Aston Martin factory specification (verify refrigerant spec and capacity in factory documentation). Test A/C system operation at various temperature settings and blower speeds.

Reassembly

1. All dashboard fasteners must be torqued to specification to prevent squeaks and rattles.
2. Verify all electrical connectors are fully seated and locked before testing systems.
3. Test all dashboard functions before considering the job complete: HVAC controls, instrument cluster, audio, navigation, airbag indicator light behavior.
4. Check for coolant leaks at heater hose connections after first warm-up cycle.
5. Verify heater output temperature reaches expected levels at maximum heat setting.
6. Inspect coolant level daily for the first week of operation to detect any slow leaks.

Verification

• Start engine and verify no coolant leaks at heater hose connections at the firewall.
• Verify coolant level remains stable in expansion tank after engine reaches operating temperature.
• Test heater operation: set HVAC to maximum heat and maximum blower speed. Verify hot air output from all vents within 5 minutes of cold start.
• Test A/C operation: set HVAC to coldest setting and maximum blower. Verify cold air output and proper compressor cycling.
• Verify all blend door functions operate correctly through full range of temperature settings.
• Check for coolant odor in cabin during heater operation (indicates leaking heater core or connections).
• Verify instrument cluster, audio system, navigation, and all dashboard controls function normally.
• Verify airbag warning light behavior: light should illuminate briefly at key-on then extinguish if system is functioning correctly.
• Test all seat functions including power adjustment and heating (if equipped).
• Check for any dashboard squeaks or rattles over rough road surfaces.

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