Multiple Warning Lights Plague VW Tiguan: Diagnose Guide

I had a similar problem with my 2018 VW Golf TDI last year. As someone with moderate experience working on cars, I first tried using my own OBD-II scanner, which showed multiple fault codes related to the control module. The symptoms were exactly like yours, engine light illuminated and various warning messages popping up across different displays. Initially thought it might be a sensor issue, but after consulting with my regular workshop, they identified incorrect vehicle coding as the root cause. The diagnostic process involved: 1. Complete system scan 2. Control module verification 3. Reset codes after proper recoding 4. Test drive to confirm fix Total repair cost was 360€, which included diagnostic time and the complete recoding procedure. The issue hasnt returned since the fix. Before suggesting more specific solutions, could you share: Have you had any recent repairs or updates? Which specific warning messages are you seeing? Does the vehicle show any performance issues? Did you already scan for fault codes? If yes, which ones appeared? This information would help determine if your issue matches what I experienced with my Golf.

Thanks for sharing your experience. My Tiguan was last serviced two months ago with no issues reported. Since then, no repairs or updates were done. The scan tool revealed fault codes P0401 and P2015, with additional messages about reduced engine power. The vehicle struggles during acceleration and occasionally goes into limp mode. The malfunction indicator stays constantly lit, unlike the sporadic warnings I got initially. The dealer workshop wait time is currently three weeks, so gathering information from others experiencing similar control module issues helps plan next steps.

Thanks for providing those specific fault codes. On my Golf, I actually encountered P2015 as well, its commonly tied to the intake manifold runner position sensor. The P0401 suggesting EGR flow issues wasnt present in my case though, which explains why your symptoms are more severe than what I experienced. After using my diagnostic scanner again on my car today, I can confirm the fault codes from my previous issue were different from your combined P0401/P2015 situation. Your symptoms, especially the limp mode and power reduction, point more toward a hardware problem rather than the coding issue I dealt with. Based on the engine diagnostics results and symptoms you described, this seems more serious than my previous control module issue. While waiting for the workshop appointment, I would avoid any heavy acceleration or long trips since these fault codes often indicate intake system problems that could worsen. The check engine light staying constantly illuminated also suggests this needs professional attention rather than the simpler fix I needed. When these codes appear together, its often related to the intake manifold and EGR system working incorrectly, likely requiring component replacement rather than just recoding.

I appreciate the detailed feedback. Those fault codes certainly point to something more complex than I initially hoped. The constant engine light and performance issues definitely suggest a hardware problem rather than just a software glitch. The scan tool readings match what you experienced with P2015, though my additional P0401 makes the diagnosis more concerning. Since the intake and EGR systems seem involved, I will avoid pushing the engine hard until the workshop can properly diagnose it. While waiting for my dealer appointment, I will keep monitoring with my diagnostic scanner for any new fault codes. The control module data should help the technicians pinpoint whether its primarily an intake manifold issue or if the EGR system is the main culprit. Given the reduced power and limp mode episodes, this seems worth the 3-week wait for proper dealer diagnosis rather than attempting temporary fixes. At least having these specific codes helps explain the multiple warning messages I first noticed.