RS5 Speedometer Fault Code: Readiness Test Required

Last month my 2018 RS4 had similar symptoms with the speedometer showing errors. The onboard diagnostics revealed incomplete system readiness, which typically occurs after disconnecting the battery or clearing fault codes. The issue requires completing a proper drive cycle to reset all system monitors. This means the vehicle needs specific driving conditions, steady speed, stops, acceleration phases, for the onboard diagnostics to verify all systems are working correctly. The exhaust system sensors were a particular concern, as they need multiple heat-up and cool-down cycles to achieve readiness status. In my case, it turned out to be a faulty wheel speed sensor causing the speedometer issues and preventing the completion of the vehicle inspection protocols. This is not typically a serious problem, but it needs proper diagnosis and repair to pass emissions testing and ensure all safety systems function correctly. The incomplete readiness status is preventing your car from properly evaluating its systems. Recommended next steps: 1. Get a second opinion from a shop specializing in Audi diagnostics 2. Request detailed OBD scan results 3. Have them check the wheel speed sensors specifically 4. Once repaired, follow their drive cycle instructions to restore system readiness

Thanks for the detailed explanation about the speedometer and OBD readiness issues. My experience was almost identical. After replacing the wheel speed sensor, the computer reset and drive cycle process took about 3 days of normal driving to complete. The speedometer has been working perfectly since then. Just curious, do you remember roughly what you paid for the repair? Also, have you experienced any other electrical glitches since getting it fixed? My Audi is coming up for its next vehicle inspection and want to make sure everything checks out for the emissions test.

Had my wheel speed sensor issue fully resolved about 2 months ago. The onboard diagnostics now shows all readiness monitors as complete after following the prescribed drive cycle. It cost me 0 Euro since it was covered under the extended warranty. The computer reset and subsequent system readiness checks have been stable since the repair. No check engine lights or electrical issues have appeared. The car diagnostics are all showing normal readings during regular scans. Getting ready for emissions testing should be straightforward now that your readiness monitors are set. Just maintain regular driving patterns and avoid disconnecting the battery, which would trigger another drive cycle requirement. Your symptoms matched mine exactly, the speedometer errors were the first sign, and completing the drive cycle after the sensor replacement fixed everything. The onboard computer just needed time to verify all systems were functioning correctly through normal driving conditions.

Just wanted to give a final update on my Audi situation. Took it to a different shop specialized in car diagnostics and had a much better experience. The repair cost was 450 Euro for parts and labor to replace the faulty wheel speed sensor. After the fix, I followed their instructions for the drive cycle, basically just drove normally for about 3 days. All system readiness monitors are now showing complete on the onboard diagnostics, and the speedometer works perfectly. No more error messages or electrical glitches since then. Really relieved everything checked out before my upcoming vehicle inspection. The new shop also did a complimentary emissions test scan to confirm all systems are ready for the official test. Much better service than my first mechanic who couldn't even explain what was wrong. Looking back, the incomplete system readiness was definitely a blessing in disguise, helped catch the sensor issue before it could cause bigger problems. If anyone else runs into similar speedometer errors, definitely get it checked by a shop that knows their diagnostics.