Figuring out what you actually need before you start searching
People usually come at this from two directions. Either their A6 has a weird electronic gremlin and they need the wiring diagram, or they picked up a used Bentley and want to know what maintenance intervals to follow. Both are valid. The problem is most of what floats around online is either a watermarked PDF you can barely read or a $40 scan that skips half the chapters. The Bentley Owner's Manual for the A6 era is essentially the same document platform Audi used across most of their C-class lineup from roughly 2005 to 2011. It covers everything from fuse layouts to torque specs on the timing chain tensioners. If your car is a 2007 C6 generation A6, the Bentley manual you want is the one labeled for both A6 and A4 models with the relevant engine code stamped on the cover page. Don't bother with the B7-only section if you have a C6, because the suspension geometry and DSC integration are completely different.
Where to get the Audi A6 Bentley Manual without wasting money
The most complete version I've found is the one bundled inside the OEM service portals, but you don't need to pay for those. There are community-maintained repositories where people upload the dealer-quality PDFs. The file is usually around 80 to 120 megabytes depending on whether it includes the workshop sections. The owner-only version runs closer to 40 megabytes. I'd grab the full thing even if you just want the owner sections, because the index cross-references the technical data and having the full document means you're not constantly switching between two files. One site worth bookmarking is audiworld.org/forums, where members have archived the scans. The file naming is inconsistent, so look for something with "Bentley" and "A6" in the title and a date stamp after 2006. If the filename just says "owner manual" without the Bentley branding, it's probably a generic Audi one and might be missing the Quattro-specific sections.
What most people miss in the manual that costs them time later
The service interval section in the Bentley manual is misleading if you read it straight. The factory-recommended oil change interval is 20,000 miles or two years. Nobody who actually owns one of these cars follows that. The 2.0T FSI engines from that era have known carbon buildup issues on the intake valves, and running long intervals makes it worse. Most people I know switch to 7,500-mile intervals with full synthetic, which is what the manual tacitly acknowledges in the severe service schedule buried in Appendix D. Another thing the manual doesn't emphasize enough is the timing chain stretch procedure on the 3.2 FSI and 4.2 V8. The Bentley documents the replacement interval as a guideline, but the actual diagnostic flow requires measuring the chain tensioner stroke with a specific tool. If you just eyeball it and replace the chain because you hear rattle at cold start, you'll waste about $600 in parts and three hours of labor on a component that might not have been the problem. The tensioner itself fails more often than the chain stretches. I learned this the hard way on my 2008 3.2, where I replaced the entire timing assembly and the old chain measured within spec. The tensioner was the culprit and cost $85 instead of $1,800.
Get the Full Details
Using the manual for actual diagnostics
The wiring diagrams in the Bentley section are organized by system, not by physical location on the car. This took me a while to get used to. If you're tracking down a parasitic battery drain on a 2006 A6 and you look for the fuse box layout expecting to find it mapped to the actual trunk location, you won't. The diagrams use circuit topology. You need to cross-reference the component locations table first, then jump to the relevant schematic. The index page at the front of each section has a quick lookup chart that maps each control module to its diagram sheet number. The OBD-II trouble codes section is also incomplete. Audi didn't publish every dealer-only code in the owner's manual. If you're seeing a P162F or some of the internal network communication codes, you'll need a VCDS or OBDeleven setup to read the manufacturer-specific codes. The Bentley manual covers the standard codes adequately for basic issues, but anything involving the transmission adaptive learning values or the air suspension height sensor calibration won't be there.
When the manual isn't enough and what to do instead
For anything beyond routine maintenance, the Bentley manual hits a wall. Suspension bushing replacement torques for the multi-link rear on the C6 are listed, but the procedure requires pressing out specific pins in a certain order or you'll crack the aluminum control arm. The manual doesn't show that detail. You'll find it in the TIS portal or in forums where someone has documented the teardown with photos. The same goes for coding changes. If you want to activate hidden features like individual seat memory locking or change the mirror dip-on-reverse behavior, the Bentley manual has exactly zero information on that. That's all in the coding databases, and getting it wrong can lock up modules. I'd recommend sticking to basic maintenance and mechanical troubleshooting with the manual and turning to specialized tools or professional help for the electronics layer. The file itself can be viewed on any device. I keep mine open on a tablet in the garage because the search function saves you from flipping through 900 pages looking for a torque spec. Press Ctrl-F and type the engine code, like "BDW" or "CMXA," and it pulls up every relevant section including bolt patterns, seal types, and fluid capacities for that specific powertrain. That single trick probably saves me more time than reading the whole thing cover to cover.
