A 2009 DB9 Coupé on the Gaydon-era VH platform, running the AML 5.9-litre V12 (AM04) — an engine managed as two independent six-cylinder engines, each with its own Powertrain Control Module. Everything documented here is first-hand: work carried out on this car, faults diagnosed on this car, and the reference knowledge accumulated along the way.
AstonPi — Raspberry Pi 5 CarPlay Head Unit
April 2026 · Live in car 29 April
A ground-up wireless CarPlay head unit: Pi 5 + NVMe on a CarPiHat Pro with ignition-controlled power, a Burr-Brown DAC, and a custom dark theme over react-carplay. The whole boot and shutdown shows one continuous breathing AM logo — no black frames, no "No Signal", no console text — with a per-stream volume mixer, rotary knob control, and a clean splash-held shutdown with ignition-abort. Full build log including the boot-time research and the hard-won Pi 5 lessons.
Live in car ✓
Project build log →
V12 Post-Service Misfire — Blocked Injector After Ultrasonic Cleaning
April 2026
After a full plug and coilpack replacement (both manifolds off, all 12 injectors out and ultrasonically cleaned), the engine returned to running with misfires on the passenger bank only. Seven diagnostic stages traced it to a single injector blocked by debris that resettled after cleaning — electrically perfect, invisible to the ECU, delivering no fuel. Includes the twin-ECU cylinder mapping diagram, the P0305 ghost-code explanation, and the coast-down relearn procedure.
Resolved ✓
Full diagnostic report →
Hard-won knowledge distilled from the diagnostic work — the stuff that isn't in the workshop manual. Collected on a single reference page: