VW Phaeton Ignition Issues: Symptoms and Solutions

Having moderate experience with VW repairs, I encountered a similar issue with my 2009 VW Passat diesel. The symptoms you describe match exactly what I experienced, inconsistent starting and rough running when the ignition key was turned. Initially thought it was the ignition coil, but after taking it to the workshop, they diagnosed a blown fuse in the ignition circuit. The repair was straightforward and cost 52€ including parts and labor. Since the fix, the car has been starting reliably with no issues. Before suggesting specific solutions for your Phaeton, could you share: Any warning lights appearing on the dashboard? Does the key turn smoothly in the ignition switch? Have you noticed any electrical issues with other systems? How long has this been happening? These details would help determine if your issue is similar to what I experienced or potentially something different. The Phaeton shares many electrical components with other VW models, but its systems can be more complex. Consider having a diagnostic scan done first, as starting issues can stem from various causes beyond just the ignition system.

Latest service was at 83000km. The starting issue has gotten worse since my initial post. The ignition switch now feels stiff when turning the key, and I noticed a check engine light briefly flashing before disappearing. The electrical problems seem isolated to the starting system, all other electronics work fine. The car electronics diagnosis revealed fault codes related to the ignition system. My local garage quoted 380€ for replacing the ignition switch and coil, but I wanted to check if this matches what others paid for similar repairs. Would replacing just the ignition switch be enough, or should I follow their recommendation to change both components? The car started fine before these issues began about two weeks ago.

Thanks for the additional details. Since my Passat repair, I have learned quite a bit about VW ignition systems. When I first had similar symptoms, I also got a quote for both the ignition switch and coil replacement. However, in my case, replacing just the ignition switch resolved the issues completely. The stiff key turning sensation you describe is a classic symptom of a failing ignition switch. The brief check engine light also matches the behavior I experienced before the repair. For the Passat/Phaeton ignition switch replacement alone, I paid 220€, which included labor. Based on your description and my experience, I would suggest: 1. Start with just the ignition switch replacement 2. Monitor the car electronics for a few days 3. Consider the ignition coil only if problems persist The intermittent check engine light suggests the issue lies primarily with the switch. The dashboard light behavior and stiff key turning are telling signs. Unless your diagnostic scan specifically showed ignition coil problems, replacing both parts immediately might be unnecessary. The 380€ quote seems high compared to what I paid, but prices vary. Perhaps get a second opinion focused just on the switch replacement.

The dealer's quote of 380€ for both the ignition switch and coil does seem steep after reading these responses. Given that my starting issue matches what others experienced with their VWs, particularly the stiff key turn and intermittent dashboard light, I think I will follow the advice and start by replacing just the ignition switch. My mechanic agreed to quote separately for the switch replacement, coming in at 195€ including labor. This seems more reasonable compared to the experiences shared here. They can check the ignition coil condition after fixing the switch if problems continue. I scheduled the ignition switch replacement for next week. The car still starts, though it takes multiple attempts now. Will update on whether this fixes the rough running and starting problems completely. Really appreciate all the detailed feedback, especially about the diagnostic symptoms matching a faulty switch rather than necessarily needing both components replaced.