VW Sharan Battery Failure Causing Multiple System Issues

Had nearly identical symptoms with my VW Touran 2.0 TDI from 2012. The battery terminal connections were corroded, causing voltage drop across the charging system. Initially thought it was just a dead battery, but deeper inspection revealed alternator issues too. The main problems found during diagnosis: Alternator belt was worn and slipping, Battery terminals needed cleaning and replacement, Alternator voltage regulator failed, Ground strap was deteriorated These electrical problems caused similar symptoms: dim lights, hard starts, and unusual electrical system failures. The alternator issue was serious since it affected the entire charging system. The repair involved replacing the alternator, cleaning all ground points, and installing new battery terminals. Your symptoms strongly suggest a charging system problem rather than just a battery issue. The flickering lights and multiple system failures point to either a failing alternator or significant voltage drop in the circuit. Would recommend getting the charging system tested before replacing parts. Best to have a complete electrical system diagnosis done by a VW specialist who can properly test the alternator output and check for voltage drop across all major connections.

Thanks for sharing your experience. The symptoms you described match what I went through. After fixing it, my Sharan has been running great for the past 8 months with no electrical issues. Was curious about the total repair cost in your case? The alternator issue and battery terminal replacements on mine cost around 850€ total, including labor. The mechanic also found a loose ground wire that was contributing to the power supply problems. Have you noticed any other electrical gremlins since the repair was done? The voltage readings on my car have been stable, but always good to hear long-term feedback from others who had similar work done.

Glad your Sharan is running well now. The total cost for my repairs was much lower at 290€ since the issue turned out to be just a heavily discharged battery instead of alternator problems. After replacing the battery and cleaning the connections, the charging system has worked flawlessly. The mechanic did a full diagnostic and discovered the undervoltage detected by the system was caused by the old battery not holding charge properly. No alternator replacement was needed in my case, which saved significant cost compared to your repair. The battery terminal connections were cleaned as preventive maintenance, but they were not the root cause. The voltage regulator and charging system have been stable for over 2 years now, with consistent voltage readings at startup and while running. Your repair cost seems reasonable given the alternator replacement and additional electrical work needed. Sometimes what appears as similar symptoms can have different underlying causes in the charging system.

I took my Sharan to a local mechanic after getting the helpful advice here. The repair went well and fixed all the electrical problems I was experiencing. Found a VW specialist who did a thorough diagnosis before replacing parts. The total repair came to 850€ which included: New alternator with voltage regulator, Battery terminal replacement, Ground wire repair, System diagnostic testing The low voltage issues are completely resolved now. The engine starts strong, all lights work normally, and electrical systems function perfectly. No more flickering or unusual failures. The mechanic showed me the worn alternator and corroded battery connections that were causing the problems. Been driving for 8 months without any electrical problems. Regular voltage checks show the charging system is working exactly as it should. Really glad I got it properly diagnosed rather than just replacing the battery like my previous mechanic suggested.