Mercedes E Klasse Generator Problems

Sounds like a classic alternator issue. The symptoms you describe reduced power, warning light, poor starting, weak lights, and stored error all point to a problem with the charging system. Is the battery relatively new? A failing battery can sometimes put extra strain on the alternator, causing it to fail prematurely. Have you checked the voltage across the battery terminals while the engine is running? It should be around 14 volts.

Thank you for your reply! The battery is perhaps two years old, so not brand new, but not ancient either. I haven't checked the voltage myself; I wouldn't even know where to begin. Is it terribly difficult? If it is an alternator issue, is it something that must be addressed immediately, or can I delay the repair for a short while? I need the car, but 960€ is a lot of money.

I understand your concern about the cost. Think of your car's electrical system like a circulatory system. The battery is like the heart, providing the initial boost, and the alternator is like the lungs, keeping everything going. If the 'lungs' aren't working, the 'heart' will eventually give out. Driving with a faulty alternator can damage other car electronics and potentially leave you stranded. Given all the symptoms and the error code, it is best to take it to a workshop. They can confirm the alternator issue and ensure everything else is in order.

You were absolutely right! I took my Mercedes to a workshop. It was indeed a defective generator and the charging system wasn't working correctly. They replaced it, and now everything is back to normal. Thank you for your advice; I appreciate it!