Starter Solenoid

Replace the starter solenoid on a 2009 Aston Martin DB9 6.0L V12, requiring removal of underbody panels, exhaust components, and access to the starter motor assembly from beneath the vehicle.

Warnings

Tools required

Parts

• Starter solenoid assembly × 1 — Use OEM Aston Martin specification or Bosch equivalent
• Solenoid mounting hardware kit (if corroded) × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake.
2. Ensure engine and exhaust system are completely cool to touch.
3. Raise vehicle on lift or support securely on jack stands at manufacturer-specified lift points.
4. Remove engine undertray panels - locate and remove Torx fasteners securing all lower underbody panels for access to starter area.
5. Disconnect battery negative terminal first, then positive terminal. Store cables away from battery posts.

Procedure

1. 1

   Remove Engine Undertray and Access Panels
   From beneath the vehicle, identify and remove all undertray panels that obstruct access to the rear of the engine at the flywheel housing where the starter is mounted. These panels are typically secured with T30 or T40 Torx fasteners. Check panel perimeter and along any joining seams for all fastener locations. Remove panels carefully and store fasteners organized by location. Note: Organize fasteners by panel location to simplify reassembly.
2. 2

   Disconnect Battery Cables
   Disconnect the negative terminal first at the battery (verify battery location — typically in the trunk on the DB9 — and correct socket size from documentation). Move cable away from terminal. Then disconnect positive terminal. Wait minimum 15 minutes for system capacitor discharge before proceeding.
   Torque spec

   Battery Cable Nut14 Nm (10 lb-ft)
3. 3

   Access Starter Motor Location
   Locate the starter motor at the rear of the engine where it engages the flywheel/flexplate ring gear at the engine's flywheel housing. Note that the 2009 DB9 uses a rear-mounted transaxle connected by a torque tube, so the starter is NOT mounted to a conventional engine-to-transmission bellhousing; verify the exact mounting location and side against Aston Martin service documentation before proceeding. The V12 configuration places the starter in a confined area; note the routing of all electrical connections before proceeding. right-side exhaust manifold. You may need to remove or loosen heat shields secured with E-Torx or Torx fasteners for adequate access. Note the routing of all electrical connections before proceeding. Note: Locate the starter motor at the rear of the engine where it mates to the flywheel housing/torque tube (this vehicle uses a rear transaxle, so the starter is NOT at a conventional front bellhousing). Confirm exact side and position against OEM documentation before proceeding. Note: Locate the starter motor mounted to the rear of the engine block at the flywheel housing. Note that the 2009 DB9 uses a rear-mounted transaxle, so the transmission is NOT bolted directly to the engine; the starter engages the flywheel ring gear at the engine's flywheel housing. Confirm exact side and position against Aston Martin service documentation before proceeding.
4. 4

   Remove Exhaust Heat Shield (if necessary)
   If a heat shield obstructs access to the starter motor, remove the fasteners securing it. These are typically E10 or E12 E-Torx fasteners. The shield may be a single piece or multi-section assembly - check all edges for fasteners. If only partial removal is needed, loosen fasteners sufficiently to pivot shield out of working area.
5. 5

   Disconnect Starter Electrical Connections
   Identify two main electrical connections at the starter: the large battery positive cable connection (B+ terminal nut — verify exact size against Aston Martin documentation) at the solenoid terminal, and the small signal wire connector (push-tab or small fastener). Disconnect the signal wire connector first by depressing the locking tab or removing small fastener. Then remove the nut securing the battery positive cable to the solenoid terminal. Support cables clear of working area.
6. 6

   Remove Starter Motor Mounting Bolts
   The starter motor is secured with mounting bolts accessible from beneath. Verify the exact number of mounting bolts and their head size against OEM Aston Martin documentation before beginning, as these values are not confirmed for this platform. Access may require long extensions and universal joints due to confined space. Remove upper bolt first, then lower bolt(s), while supporting the weight of the starter motor to prevent it from falling. Note: The starter motor is secured to the flywheel housing with mounting bolts (count and head size to be confirmed against OEM documentation for this platform). Access may require long extensions and universal joints due to confined space. Remove upper bolt first, then lower bolt(s), while supporting the weight of the starter motor to prevent it from falling. Note: The starter motor is secured to the engine flywheel housing with mounting bolts accessible from beneath (verify exact count and hex size against Aston Martin documentation).
   Torque spec

   Starter Mounting Bolt45 Nm (33 lb-ft)
7. 7

   Remove Starter Motor Assembly
   With all mounting bolts removed and electrical connections disconnected, carefully withdraw the starter motor from the flywheel housing. The starter nose engages the flywheel housing bore and may require slight rotation and manipulation to clear surrounding components. Lower the assembly carefully once clear. Place on clean work surface.
8. 8

   Remove Solenoid from Starter Body
   With starter motor on workbench, locate the solenoid mounted to the starter body. The solenoid is typically secured with two or three fasteners; verify the exact count, drive type, and size against Aston Martin/starter manufacturer documentation before removal. Note the orientation and position of the solenoid relative to the starter body and mounting ears. Remove fasteners and carefully separate solenoid from starter body. The solenoid plunger engages the starter drive mechanism - withdraw carefully to avoid damaging engagement points.
9. 9

   Inspect Starter Motor Components
   With solenoid removed, inspect the starter motor drive engagement mechanism for wear or damage. Check the solenoid mounting surface on starter body for corrosion or damage. Clean mounting surfaces with wire brush if needed. Inspect electrical terminal studs on starter body for damage or excessive wear.
10. 10

    Install New Solenoid to Starter Body
    Position the new solenoid on the starter motor body, ensuring the plunger properly engages the starter drive mechanism and the solenoid is oriented correctly with terminal studs positioned as original. Install mounting fasteners and tighten evenly. If original fasteners are corroded, use new hardware from mounting kit. Tighten solenoid mounting fasteners to the OEM-specified torque for this starter assembly (verify fastener size and torque against documentation before final tightening). Note: Tighten solenoid mounting fasteners to the manufacturer specification. Confirm the exact fastener size and torque against OEM documentation, as these values are not verified for this starter assembly. Note: Tighten solenoid mounting fasteners to the starter/solenoid manufacturer specification (verify exact value and fastener size from OEM documentation).
11. 11

    Reinstall Starter Motor Assembly
    Carefully guide the starter motor assembly back into position at the engine flywheel housing. Align the starter nose with the flywheel housing bore and engage fully. The mounting bolt holes must align with threaded bosses in the flywheel housing. Manipulation and slight rotation may be required for fitment in the confined space.
12. 12

    Install Starter Mounting Bolts
    Install starter mounting bolts and hand-tighten initially. Ensure starter is fully seated against bellhousing before final tightening. Tighten mounting bolts to the OEM-specified torque using a torque wrench. Confirm the exact torque value against Aston Martin service documentation before final tightening, as this value is not verified for this platform. If using extensions and universal joints, account for deflection in torque measurement. Note: Tighten mounting bolts to the OEM-specified torque for this starter (verify against Aston Martin documentation before final tightening, as these thread into an aluminum housing). Note: Tighten mounting bolts to Aston Martin specification using a torque wrench (verify exact value from OEM documentation before final tightening).
    Torque spec

    Starter Mounting Bolt45 Nm (33 lb-ft)
13. 13

    Reconnect Starter Electrical Connections
    Reconnect the large battery positive cable to the solenoid terminal stud. Install retaining nut and tighten to the OEM-specified torque. Confirm the exact value against Aston Martin documentation, as this spec is not verified for this platform. Then reconnect the small signal wire connector, ensuring it clicks or locks into position fully. Verify both connections are secure and cables are routed clear of exhaust components and moving parts. Note: Install retaining nut and tighten to the OEM-specified torque for the solenoid terminal stud (verify against documentation; do not overtighten to avoid damaging the stud). Note: Install retaining nut and tighten to the starter manufacturer's specification for the B+ terminal stud (verify exact value from OEM documentation; do not overtighten).
14. 14

    Reinstall Heat Shield and Access Panels
    If heat shield was removed or loosened, reposition it and install all fasteners. Ensure shield does not contact starter motor or electrical connections. Reinstall all undertray panels removed during access, securing with original Torx fasteners. Verify all panels are properly seated and fasteners are tight.
15. 15

    Reconnect Battery and Test
    At the battery location, reconnect the positive terminal first, then the negative terminal. Tighten battery cable nuts to the OEM-specified torque, taking care not to overtighten and damage the terminals. Confirm exact values against Aston Martin documentation, as these specs are not verified for this platform. Do not overtighten to avoid damaging battery terminals or cable ends. Note: Tighten battery cable nuts to the OEM-specified torque (verify against Aston Martin documentation). Do not overtighten to avoid damaging battery terminals or cable ends. Note: Tighten battery cable nuts/terminal bolts to Aston Martin specification (verify exact values from OEM documentation; do not overtighten to avoid damaging terminals).
    Torque spec

    Battery Cable Nut14 Nm (10 lb-ft)

    Battery Terminal Bolts6 Nm (4 lb-ft)

Reassembly

1. Reinstall all components in reverse order of removal.
2. Ensure all electrical connections are secure and properly routed away from heat sources.
3. Verify all undertray panels are reinstalled with all fasteners to prevent rattles and ensure proper aerodynamics.
4. Double-check that no tools or parts were left in the engine bay or under the vehicle.

Verification

• With vehicle still raised and in Park/Neutral, turn ignition key to START position and verify starter engages and cranks engine smoothly without abnormal noise.
• Listen for proper solenoid engagement click before starter motor spins.
• Start engine and verify normal operation with no warning lights related to charging system.
• Shut off engine and inspect starter area for any fluid leaks or loose connections.
• Lower vehicle and perform final visual inspection of work area.
• Test start engine from cold several times to confirm reliable starter operation.

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