Mercedes B Klasse Diesel Refusing to Start

I had a similar problem with my B Klasse not too long ago. It also wouldn't start and gave me some kind of engine error. I'm not sure if it's exactly the same issue, but did you really check the battery cable connections? I mean, really give them a good wiggle and make sure they're tight? That was my problem.

When you say 'really check', what exactly did you do? I visually inspected them, and they appeared fine. Did you clean them, or did you use a multimeter or something? Just trying to understand the level of detail I should be looking at.

Well, I'm definitely no mechanic, so I didn't use any fancy tools. But I did disconnect the cables, gave them a good clean with a wire brush (just a cheap one I had lying around), and then made sure they were really, really tight when I reconnected them. It might not be your problem, but it's worth a shot before taking it to a workshop.

Thanks for the tip. I double-checked the battery cable connections like you suggested, gave them a proper clean, and tightened them up. Turns out that was indeed the problem! The car started right up. Apparently, the connection wasn't great. Cost me 155€ at the workshop. Appreciate the help!