Audi Q2 Battery Drain Causing Multiple System Failures

Had similar electrical system issues on my 2015 Audi A3 1.4 TFSI. The symptoms match what typically happens when the battery management sensor fails, flickering lights, unusual error messages, and starting problems. The battery drain becomes excessive because the car cant properly monitor power distribution. The battery sensor defect is actually a common fault in VAG cars from this period. When mine failed, the electrical system would get confused about the battery charge state, leading to similar symptoms even with a perfectly good battery. Initial testing might point to a dead battery, but replacing just the battery often doesnt solve the underlying issue. The proper fix requires: 1. Full electrical system diagnostic scan 2. Testing the battery management sensor 3. Checking charging system components 4. Verifying alternator output In my case, what seemed like simple battery failure turned out to be the faulty sensor causing system-wide issues. This isnt a minor problem, leaving it unfixed can damage other electrical components over time. Would strongly recommend having it properly diagnosed at a shop with VAG-specific diagnostic equipment. The battery management system is integrated with multiple control modules, so accurate testing is essential.

Thanks for sharing those details about the sensor issue. I also struggled with my Q2 last year and had nearly identical symptoms. The fix ended up being a combination of a dead battery and corroded battery terminals that were preventing proper charging. The electrical system would show unusual errors because of the inconsistent power supply. Did the repair cost include both parts and labor? Mine came to around 450 Euro total, but wondering if prices have changed since then. Have you had any recurring electrical issues since getting it fixed?

The repair for my A3 was much more straightforward once the correct diagnosis was made. The total cost came to 315 Euro which covered both the battery sensor replacement and labor. This resolved the battery drain issues completely, no more problems with discharged battery conditions or electrical gremlins since the fix. I had initially suspected a failing battery when dealing with the vehicle battery problems, but getting the sensor replaced was the right call. The electrical system is now working perfectly, no more flickering lights, error messages, or charging problems. The battery maintains proper charge levels and the car starts reliably every time. For anyone facing similar symptoms, its worth checking the battery management sensor before just replacing the battery. A faulty sensor can make a good battery appear discharged and cause all sorts of electrical system confusion. The 315 Euro repair cost was worth every cent to resolve these issues properly. The key was finding a shop that correctly identified the sensor as the root cause of the battery drain rather than just suggesting a new battery. Going on 8 months now with zero electrical problems since the repair.

I took my Q2 to a different mechanic this time who actually found the real problem. The battery management sensor was completely shot, just as you described. They did a full diagnostic scan which showed multiple electrical faults stemming from the faulty sensor. The total repair came to 380 Euro including a new battery sensor, labor, and system testing. Much better than my previous mechanic who just kept suggesting battery replacements without finding the root cause of the battery drain. The low battery warnings and electrical glitches completely disappeared after fixing the sensor. Car starts perfectly now and maintains proper charge. Its been about 2 months since the repair with zero issues. The car battery is holding charge like it should. Really glad I got a second opinion instead of throwing parts at the problem. A proper diagnosis made all the difference in resolving the dead battery symptoms. The investment in finding a competent shop definitely paid off in the end.