SQ8 Battery Chaos: Multiple System Failures Point to Alt

Had similar symptoms on a 2020 S7. The unusual system failures and circuit protection warnings pointed to a severe electrical issue beyond just a weak battery. The alternator was actually fine, the root cause was a failing voltage regulator causing power surges through the electrical system. These power spikes were triggering the car ECU protection measures, leading to those unusual system shutdowns. What starts as battery problems often indicates deeper electrical system issues. The high voltage spikes can damage multiple control modules if left unchecked. In my case, the voltage regulator replacement solved the cold start problems and erratic system behavior. Would suggest having the charging system fully tested, focusing on: Voltage regulator output, Battery cell health, Ground connection integrity, Car ECU voltage readings This type of electrical issue needs proper diagnosis with specialized equipment. A basic battery test wont reveal the full scope of the problem. The symptoms match classic voltage regulation failure rather than alternator issues. Definitely worth getting it checked properly, electrical gremlins can cascade into expensive control module failures if the root cause isnt fixed.

Thanks for sharing your experience with the voltage regulator issue. I faced similar car battery problems with my Audi recently. The power surge symptoms were almost identical, though my circuit protection system caught most issues before any real damage. Did you track how much the full diagnosis and repair cost in the end? Also curious if everything has been stable with the electrical systems since the fix. High voltage problems can sometimes cause lingering issues that show up later.

Thanks for asking about the repair costs and follow-up. Since seeing the mechanic, the overvoltage warnings completely cleared up. The final bill came to 290 Euro for addressing the heavily discharged battery issue. The car electronics have been working flawlessly for the past few months. No more unusual system failures or circuit protection triggers. The cold starts are strong now, and all electrical systems function as they should. The thorough diagnosis was key, they detected the exact high voltage patterns causing the problems. While it seemed costly at first, preventing potential damage to multiple control modules made it worthwhile. One tip: regular voltage checks during maintenance can catch these issues early. Its much cheaper than dealing with cascading electrical failures later. All car battery related issues have stayed fixed. No lingering problems at all. If yours shows similar symptoms, addressing it quickly will likely prevent more extensive electrical damage.

I finally got my electrical issues sorted out. After reading about voltage regulator problems, I took my SQ8 to a specialized electrical diagnostics shop rather than a general mechanic. The car battery was showing signs of damage from repeated power surges. They found the circuit protection system was being overwhelmed by voltage spikes, exactly matching what others described. The complete diagnosis and repair, including a new voltage regulator and battery, cost 1250 Euro. More than expected, but worth every cent considering the potential damage to the car ECU and other modules. Been driving for two weeks now and all electrical problems have disappeared. No more cold start issues, no unusual system failures. The shop did a thorough job documenting all the overvoltage readings before and after the fix to show the problem was properly resolved. Looking back, I should have gone straight to an electrical specialist rather than trying general repairs first. Lesson learned about electrical issues requiring proper diagnostic equipment and expertise.