Multiple VW Polo Electrical Issues Signal Dying Battery

I experienced similar battery drain symptoms on my 2015 VW Golf TDI. The car battery issues started exactly like yours, dim lights, sluggish starts, and unusual error messages on the dash. After checking the battery terminals which appeared clean, the diagnostic revealed a faulty battery sensor. This component monitors charging status and power flow, so when it fails, it can cause multiple electrical problems across vehicle systems. The battery sensor defective condition is actually quite serious since it can: Prevent proper battery charging, Cause the alternator to overwork, Lead to a completely discharged battery, Trigger false error codes in various control modules The fix required replacing both the sensor and the car battery since the discharged battery had been deeply cycled too many times. The original sensor had corroded internally, providing incorrect data to the power management system. Worth noting the battery charging system on VW diesels from this generation is particularly sensitive to sensor issues. Best to have it checked soon before it leaves you stranded or causes damage to other electrical components. Before visiting a shop, you can verify if battery voltage drops significantly when starting the car. This helps confirm if its truly a battery-related problem rather than something else electrical.

Thanks for the detailed response about the battery sensor issue. Mine turned out to be exactly what you described with the faulty sensor throwing off the entire electrical system. The mechanic fixed it last week and the car runs perfectly now, no more dim lights or starting problems. Would you mind sharing what the repair cost you? I paid around 380€ for the complete fix including the new battery and sensor but wondering if that was reasonable. Just curious if you encountered any other electrical system problems since getting it sorted? The dead battery symptoms you mentioned matched my experience exactly. Really glad I caught it before getting stranded somewhere with a completely discharged battery.

Thanks for asking about the repair costs. My total bill came to 315€ for replacing the faulty battery sensor and getting the charging system back to normal. Sounds like we both caught the battery issues before major damage occurred. Since fixing the discharged battery and sensor problem six months ago, the electrical system has worked flawlessly. No more error messages, weak starts, or battery drain issues. The new sensor ensures proper battery charging and the car starts instantly every time. One tip, I now regularly check the battery terminals for any signs of corrosion just to stay ahead of potential issues. A properly functioning battery sensor makes a huge difference in maintaining stable power throughout the electrical system. Your 380€ repair cost seems reasonable considering you also got a new car battery. These specialized sensors arent cheap, but replacing them is far better than risking damage to other electrical components from incorrect charging.

After reading about similar battery drain symptoms online, I finally took my car to the mechanic last week. Turned out the problem was exactly as described, a faulty battery sensor causing all sorts of electrical gremlins. The repair process was straightforward. They diagnosed the vehicle battery issues within an hour using their specialized equipment. The mechanic showed me how the old sensor was sending incorrect signals, leading to the discharged battery and system errors. Total cost came to 380€ for a new car battery, sensor replacement, and diagnostic time. Been driving for a week now and what a difference, strong starts, bright lights, and no more dashboard errors. The speedometer and other gauges work perfectly again. Really glad I checked here first instead of just replacing the battery terminals or jumping to conclusions. Going to keep an eye on the new battery charging system, but so far everything is working exactly as it should. Money well spent to avoid being stranded with a complete battery failure.