VW Fox Diesel Stalling Issues, Warning Light Alert

I had an almost identical issue with my 2013 VW Polo diesel last winter. Have some experience with basic maintenance but needed professional help for this one. The engine stalling was really similar to what you describe, unusual shutdowns while driving and problems with the idle stop system not restarting properly. First thought it was the eco mode acting up, but the workshop diagnosed a severely discharged battery that was unable to maintain proper voltage. Had it fixed at a certified workshop, they tested the charging system, replaced the battery, and recalibrated the start-stop system. Total cost was 290€ including parts and labor. Car has been running perfectly since then, no more stalling issues. Could you share: Current battery age and maintenance history, Whether the starter motor makes any unusual sounds, If the issues happen more frequently in cold weather, What error codes you pulled from the system This info would help determine if your situation matches what I experienced. Battery issues often show similar symptoms to hybrid vehicle control problems, so getting the exact diagnosis is important.

Last service was at 72082km and the dealer already checked all fuses and battery connections. Pretty sure its not a car battery issue since I had it replaced last year. The starter motor sounds normal when starting from cold, but the automatic restart is really unpredictable, sometimes it works fine, other times nothing happens. The error codes point to P0562 (system voltage low) and P0563 (system voltage high), which seems strange having both. Temperature doesnt seem to affect it much. Just not sure if I should trust the dealer saying I need a complete starter motor replacement when the cold starts are fine. Feels like the idle stop system might be the real culprit here.

Thanks for the additional details about your Fox. Having gone through this with my Polo, those error codes actually make a lot of sense together, they typically indicate an unstable charging system rather than just a battery issue. While the start-stop system could be causing problems, my experience suggests we should look at the alternator first. When my Polo showed similar symptoms, normal cold starts but unreliable automatic restart, the alternator was actually delivering inconsistent voltage. This explains both the low and high voltage codes you mentioned. The dealer might be jumping to conclusions about the starter motor. Since your cold starts are working fine, this points more toward a charging system problem interfering with the start-stop functionality. My alternator replacement cost 420€ and completely resolved both the engine stalling and automatic restart issues. Would recommend: Getting the alternator tested specifically, Having the voltage regulator checked, Requesting a detailed charging system diagnosis The symptoms really mirror what happened with my car, trust your instinct about questioning the starter motor replacement. A failing alternator can make the start-stop system behave erratically while still allowing normal cold starts.

Being really concerned about those fault codes now. The alternator theory makes way more sense than what the dealer suggested about the starter motor. Explains why cold starts work fine but the start-stop system keeps acting up. Just booked another garage for a second opinion, specifically asking them to test the alternator and charging system. Want to be absolutely sure before spending money on repairs. The engine stalling while driving is getting worse and definitely dont want to risk getting stranded somewhere. Really helpful to hear from someone who dealt with similar issues. Will update once I get the alternator tested properly. Kind of relieved its probably not the starter motor, that replacement quote from the dealer was way higher at 780€. Even if it turns out to be the alternator, still cheaper than what I was quoted. Just hope they can fit me in soon since the idle stop failures are becoming more frequent. Getting tired of the warning lights coming on during my commute.