Diagnostic Scan

Perform a diagnostic scan on a 2009 Aston Martin DB9 using an OBD-II scanner to retrieve stored fault codes, pending codes, and freeze frame data from the vehicle's electronic control modules.

Warnings

Tools required

Preparation

1. Park vehicle on level ground and engage parking brake
2. Turn off all electrical accessories (radio, climate control, lights)
3. Ensure ignition is in the OFF position before connecting scanner
4. Locate the OBD-II diagnostic port under the driver's side dashboard, to the left of the steering column near the footwell

Procedure

1. 1

   Connect diagnostic scanner
   Plug the OBD-II scanner connector into the vehicle's diagnostic port. The port is a 16-pin trapezoid OBD-II connector located under the driver's side dashboard in the lower footwell area. Refer to the vehicle owner's manual to confirm exact port location before connecting. Ensure the connection is fully seated and secure.
2. 2

   Turn ignition to ON position
   Turn the ignition key to the ON/RUN position (second position) without starting the engine. All dashboard warning lights should illuminate briefly. Wait for the scanner to power on and establish communication with the vehicle. This may take 10-30 seconds depending on the scanner model.
3. 3

   Initialize scanner and identify vehicle
   Allow the scanner to auto-detect the vehicle or manually select 2009 Aston Martin DB9. Verify that the scanner displays correct vehicle information including VIN. If communication fails, verify the scanner supports Aston Martin (Ford-era) protocols — many generic OBD-II scanners cannot fully communicate with the DB9's modules and the Aston Martin Diagnostic System (AMDS) or equivalent professional tool may be required. Also verify battery voltage is above 12 volts. Note that the 2009 DB9 was developed during the Ford ownership era and shares some Ford-sourced electronics, so full system access generally requires the Aston Martin dealer tool (Aston Martin Diagnostic System / ADS) or a professional scanner with Aston Martin coverage; generic OBD-II scanners access only powertrain/emissions data. Note: If communication fails, check scanner compatibility with Aston Martin/Ford-based systems and verify battery voltage is at a healthy level (approximately 12.6 volts at rest). Note that generic OBD-II scanners may only access generic emissions-related powertrain codes; full system access on the DB9 typically requires an Aston Martin-specific or dealer-level diagnostic tool (such as an AMDS/Ford IDS-based system). Note that the 2009 DB9 was developed during the Ford ownership era and shares some Ford-sourced electronics, so full system access generally requires the Aston Martin dealer tool (Aston Martin Diagnostic System / ADS) or a professional scanner with Aston Martin coverage; generic OBD-II scanners access only powertrain/emissions data.
4. 4

   Read diagnostic trouble codes
   Navigate to the 'Read Codes' or 'Scan' function on the scanner. Select to read stored/current codes first. Record all DTCs (Diagnostic Trouble Codes) displayed, including the code number (e.g., P0301), description, and status (current, pending, or permanent). Note the number of codes present in each system.
5. 5

   Check pending and permanent codes
   Access the pending codes menu to identify faults that have occurred but haven't met the criteria to set a permanent code. Also check for permanent codes which cannot be cleared without proper repair and drive cycle completion. Record all pending and permanent codes separately from current codes.
6. 6

   Retrieve freeze frame data
   For each stored code, access the freeze frame data which captures operating conditions at the moment the fault was detected. Record critical parameters including engine RPM, vehicle speed, coolant temperature, fuel trim values, and throttle position. This data is essential for diagnosis.
7. 7

   Access additional control modules
   If using an advanced scanner capable of full system access, navigate to additional modules beyond powertrain (engine and transmission). Scan the ABS module, airbag/SRS module, HVAC module, instrument/central electronic modules, and body control module (note: a suspension control module is only present if the vehicle is equipped with optional adaptive damping). Record any codes present in these systems. Note that basic OBD-II scanners will only access powertrain codes.
8. 8

   Check live data and system readiness
   Access live data stream to verify sensor readings and system operation. Where supported, check that emission system monitors show 'Ready' status for inspection purposes. Note that readiness monitor support on the DB9 may be limited compared to mainstream vehicles. If monitors show 'Not Ready', the vehicle may require a complete drive cycle. Record any monitors that are incomplete.
9. 9

   Document all findings
   Create a comprehensive record of all codes, freeze frame data, module statuses, and live data anomalies. Include date, mileage, and any customer complaints. Take photos of scanner display if possible. This documentation is essential for proper diagnosis and repair tracking.
10. 10

    Disconnect scanner
    Exit the scanner software properly using the appropriate menu option. Turn the ignition to OFF position. Disconnect the scanner from the OBD-II port. Store the scan data according to shop procedures or customer records.

Reassembly

1. No disassembly required for this procedure

Verification

• Confirm all diagnostic trouble codes have been properly recorded with descriptions and freeze frame data
• Verify scan data is saved or printed for reference during repair procedures
• Ensure no new communication errors were introduced during scanning process
• Confirm vehicle starts normally after diagnostic scan is complete

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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