Phaeton Key Fob Failure: Central Locking Issues Fixed

Had nearly identical issues with my 2006 VW Touareg V10 TDI. As someone with intermediate car maintenance experience, I recognized similar symptoms, unreliable central locking and key fob issues. Even without the low voltage warning, a weak battery in the electronic key was causing intermittent operation. The car key would work sometimes, then completely fail other times. The workshop confirmed the dead key fob battery was the culprit, though the warning hadnt triggered yet. Quick fix: had the key fob battery replaced at the workshop, total cost 37€ including diagnostic check. The central locking system worked flawlessly after that. To help troubleshoot your specific case: What exact error codes are stored? Does the key work better when held very close to the door handle? Have you noticed any other electrical issues? Worth checking the key fob battery first, its often overlooked but causes these exact symptoms. Could save you time and money before diving into more complex electrical diagnostics.

Just had my regular service at 105811km. After the battery replacement in the electronic key, everything works perfectly again. The error codes cleared automatically. Holding the key near the door handle did improve function temporarily, confirming the low voltage issue in the fob battery. No other electrical problems noticed since the fix. Total repair cost was 35€ including key battery diagnostics.

Thanks for confirming the auto key diagnosis worked out. Good to hear the battery replacement solved the keyless access issues, matches exactly what I experienced with my Touareg. The symptoms perfectly aligned with a classic low battery scenario in the key fob, especially how holding it closer to the door handle temporarily improved function. This is a telltale sign of low voltage in the car key transmitter. The automatic error code clearance after battery replacement is typical for these central locking issues. In my case, the error memory also cleared itself once proper voltage was restored to the key fob system. Your repair cost of 35€ was actually slightly better than what I paid (37€) for essentially the same fix. It shows these key fob battery replacements are fairly standardized services. Just a heads up, might be worth noting when you had this battery replaced so you can anticipate the next replacement interval. My key fob batteries typically last 3-4 years before showing these symptoms again.

Thanks for the input. Really glad I checked here before spending more on complex diagnostics. After getting the fob battery replaced during my 105811km service, the electronic key works perfectly again. The proximity test near the door handle confirmed what you all suggested about the key battery being the culprit. Central locking now works consistently and all error codes cleared on their own. Total cost was just 35€ including diagnostics, definitely worth fixing early before it completely failed. Will mark my calendar to check the key battery again in about 3-4 years based on the typical lifespan mentioned. Nice to have such a straightforward solution to what seemed like a major keyless access problem.