Audi A6 Diesel Dead Silent When Turning Key

Had similar issues with a 2009 Audi A4 2.0 TDI. Your symptoms point strongly toward battery cable connection problems rather than engine fault or fuel injection complications. The no-crank, no-click scenario typically indicates poor electrical contact. When this happened, the main battery terminals showed significant corrosion under the clamps, preventing proper current flow. The diagnosis revealed that while the battery itself tested fine, the connection points had deteriorated. The fix required cleaning both terminals thoroughly, replacing the battery cable ends, and ensuring proper torque on the connections. Though not a severe mechanical issue, poor connections can mimic more serious ECU failure symptoms and create misleading engine diagnostics readings. Key checks before visiting a mechanic: Visual inspection of battery terminals for corrosion, Check cable connections for tightness, Look for frayed or damaged battery cables, Test battery voltage The repair proved straightforward once properly diagnosed. Important to note that engine surge or starting issues often get misdiagnosed as complex electronic problems when the root cause is basic electrical connectivity. Suggest having the battery connections checked first before exploring more complex fuel system or electronic issues.

Thanks for sharing that experience. I had nearly identical battery connection issues with my A6 last winter causing engine stalling. My mechanic first suspected a fuel injection problem but it turned out to be corroded terminals too. Did your repair hold up well since then? Would be helpful to know what the fix cost in your case in case I need similar work done. My engine diagnostics showed no fault codes either which matches your experience.

After taking my A4 to the mechanic for the battery connection issues, the ECU issue was completely resolved. The total repair came to 155 Euro which covered cleaning the terminals, replacing corroded cable ends and proper reconnection. The fix has been solid with no engine stalling or starting problems since then. The mechanics confirmed what I suspected, poor electrical connections can trigger misleading engine software readings while not actually setting off check engine codes. This matches your experience perfectly. Having clean, tight battery connections is crucial for preventing false ECU failure symptoms. For proper engine diagnostics, the battery connections really need to be checked first. In both our cases, what initially seemed like complex fuel injection problems turned out to be basic electrical issues. Glad we could avoid more expensive repairs by identifying the true cause.

I took your advice and visited my mechanic yesterday. After describing the symptoms, they first checked the battery connections as suggested. Sure enough, they found heavy corrosion on both terminals and some damaged wiring near the positive cable. The repair was quick and straightforward, they cleaned both terminals, replaced the corroded cable ends, and properly torqued everything back together. Total cost came to 140 Euro, which felt reasonable considering how worried I was about potential ECU failure or major engine fault issues. Started right up after the fix and has been running perfectly since. No engine surge or starting problems at all. Really glad I checked the simple electrical issues first instead of jumping to complex engine software diagnostics. Amazing how corroded battery connections can cause symptoms that mimic serious electronic problems. The check engine light staying off makes more sense now too. Thanks again for helping point me in the right direction and saving me from potentially expensive unnecessary repairs.