Sprinter serpentine belt tensioner issue

I understand you are experiencing issues with the belt tensioner on your Mercedes Sprinter. The failure of the belt handover mechanism typically indicates a problem with the tensioner pulley or the belt tensioner assembly itself. I encountered a similar situation on a 2012 Audi A4. A thorough inspection of the tensioner, idler pulley, and serpentine belt is advisable to identify the root cause. Examine the tensioner for any signs of wear, damage, or loss of tension. Also, confirm that the timing belt is in good condition and properly aligned. What indications lead you to suspect the belt tensioner specifically? Are there any unusual noises or vibrations present?

Thanks for the quick reply! What do you mean by 'belt handover mechanism'? I'm not super familiar with the terms.

Apologies for the technical jargon. By "belt handover mechanism," I was referring to the ability of the belt tensioner to maintain consistent tension on the serpentine belt as it moves around the various pulleys (e.g., idler pulley, tensioner pulley). If the tensioner fails to maintain adequate tension, the belt can slip or even come off. Given your limited familiarity, and the potential complexity of the system, I would suggest taking it to a qualified mechanic for diagnosis and repair. A malfunctioning belt tensioner can cause significant damage if left unattended. The eventual repair cost will probably be around 455€.

Okay, thanks for confirming my suspicions! I'll take it to a workshop. Appreciate the advice!