Mercedes C Klasse Diesel Start Stop Problem

Sounds like battery trouble affecting the start-stop Modern systems are very sensitive to voltage drops Is the battery original Have you checked the resting voltage after the car has been sitting overnight A weak battery can cause errors, especially in a complex system It could also impact other systems if the voltage is unstable Have you load tested the battery

I haven't load tested the battery yet, but I can get that done What resting voltage should I be looking for after it sits overnight Also, if it is the battery, could it have damaged the starter motor with the extra work it's been doing I'm trying to understand the potential worst-case scenario

A healthy car battery should read around 12.6V or higher after sitting overnight Anything below 12.2V is suspect While a weak battery can theoretically shorten the starter motor life over time, it's unlikely to cause immediate damage However, given the symptoms and error codes, replacing the car battery is the logical first step If the problem persists after a new, fully charged car battery is installed, then further diagnostics on the starter motor or other components might be necessary Considering the potential cost of diagnosing deeper issues, the 290€ for the battery might be the best starting point

You were spot-on I replaced the car battery, and the start-stop system is back to normal No more error codes, no more engine shutdowns, and the warning light is gone I appreciate the advice; it saved me from chasing ghosts and spending a fortune on unnecessary diagnostics