Audi A4 2008–2009 Factory Service Manual

• 827-page PDF set — 452-page 3.2L engine reference; 163-page TT system-wiring guide; 72-page TT repair-information section; 42-page Audi DTC table; 37-page fuse/relay guide; 36-page electrical-component location guide; 23-page 2008–09 TT Coupe/Roadster collision-parts guide; and a 2-page dust/pollen filter procedure.
• TT/TTS repair coverage spans brakes, clutch and driveline, cooling, engine electrical/mechanical work, gasoline fuel injection, HVAC, steering, suspension, and wheel-bearing service.
• Electrical diagnosis coverage includes 81 system wiring diagrams, control-module and connector-location views, fuse/relay identification, and the J519 relay/fuse-panel change through May 2009 versus from June 2009.
• Engine-code coverage is file-specific: the TT repair-data section lists 3.2L BUB plus 2.0L BPY/BWA entries, while the 452-page BKH engine manual is separately labeled 2006 Audi A4 and should be treated as a BKH engine reference rather than TT-specific engine-code coverage.
• Major BKH engine procedures include engine removal/installation for manual-transmission configurations and the 09L automatic, engine/transmission separation, downward engine/transmission/subframe removal, assembly-stand setup, timing-chain work, cylinder-head/valvetrain service, and lubrication, cooling, and exhaust repair.
• Special service tools and illustrated references include VAS 6131 drivetrain support equipment, VAS 6095/6100/6101 assembly-stand and lifting equipment, T40069/T40070 timing tools, V.A.G 1342 oil-pressure testing equipment, and T10361 wheel-bearing tooling. The BKH file alone contains 690 numbered figures, with the TT wiring PDF adding 81 circuit diagrams.

This set combines several service references rather than one uniform model-year publication. The TT-specific electrical files are labeled 2008 or 2008–09, the collision-parts pages are labeled 2008–09, and the TT repair-information section carries 2009–2010 TT/TTS specification and maintenance tables. For major repair work, the material is suited to experienced technicians or advanced DIY owners who already understand workshop safety and have access to lifting, diagnostic, and specialty service equipment.

TT Repair, Chassis, and Electrical Detail

The 72-page TT section goes beyond routine maintenance. It covers removal and installation work on brake calipers and pads, clutch and driveline components, radiator/thermostat/water pump, alternator and starter, camshaft and valve-lifter components, catalytic converters, crankshaft seals, cylinder heads, manifolds, oil pan and oil pump, fuel filter/injectors/pump/tank, blower motor and heater core, power steering gear and pump, suspension links, struts, springs, stabilizer bars, and wheel bearings. Its reference tables cover engine identification, tune-up and fluid specifications, torque categories, wheel alignment, brake specifications, capacities, and scheduled maintenance.

The electrical files add the detail needed for fault tracing. Representative diagrams include the 3.2L Engine Performance Circuit, A/T Circuit, AWD Circuit, Power Distribution Circuit, Supplemental Restraints Circuit, and separate early-/late-production Bi-Xenon and Cornering Headlight Circuits. Component-location pages map relay panels, the engine-compartment E-box, control modules, sensors, and connector stations, while the fuse guide documents production-specific panel and relay assignments.

BKH Engine Service and Assembly Details

The separate BKH reference identifies the Simos engine-management system and provides engine-number identification, general repair notes, torque tables, inspection limits, and system-specific test data. Its repair depth includes timing-chain covers and chain drives, balance-shaft and oil-pump drive chains, crankshaft and connecting rods, piston/ring checks, cylinder-head and camshaft work, hydraulic support elements, oil-pressure testing, cooling-system draining/filling and leak testing, radiator and fan service, catalytic-converter/front-pipe work, exhaust manifolds, and oxygen-sensor access.

Two cautions show the level of mechanical detail. The 09L section warns that an incorrectly seated torque converter can damage the converter coupling and ATF pump when the engine and transmission are joined. The valvetrain material warns that incorrect crankshaft/camshaft handling with the chain drive incomplete can result in valve-to-piston contact. High-pressure fuel-system safety and cleanliness requirements are also documented before work around the fuel rail, injectors, or related high-pressure components.

The BKH PDF is specifically an Engine Mechanical reference. It identifies Simos and includes fuel-system safety information, but repeatedly cross-references the separate fuel-injection section; it should not be treated as a complete Simos pinout or fuel-injection diagnostic manual.

DTC, Parts, and Document Scope

The 42-page Audi Online Technical Library DTC file cross-references Audi numeric trouble codes with SAE P-codes and fault descriptions. The 23-page TT Coupe/Roadster parts section supplies exploded collision/body views and labor-reference data for panels, bumpers, lamps, doors, roof/convertible-top areas, suspension, underbody, and related assemblies, including TT/TTS-specific callouts. A separate dust/pollen filter procedure covers the TT filter variants.

Manufacturer credits appear on many illustrations, but several service PDFs also carry Mitchell Repair Information formatting and copyright, and the BKH file includes a third-party compilation notice. This set should therefore be described as a compiled service-information collection, not as one original Volkswagen United States, Inc. OEM publication.