Mercedes S Klasse Central Locking Problem

I appreciate you bringing this matter to the forum The symptoms you describe bear a striking resemblance to an issue I once encountered with my own S Klasse While my vehicle differs in model year from yours, the underlying systems share considerable commonality Have you observed any other anomalies accompanying this central locking malfunction? Specifically, have you noticed any irregularities with the car alarm, security system or indeed the keyless entry functions? Furthermore, have you attempted to diagnose the problem by inspecting the relevant fuses and relays associated with the locking mechanism? Although a defective cable or plug connection is a plausible explanation, I would suggest a thorough investigation before proceeding with any disassembly

You mentioned other anomalies The car alarm hasn't been triggered at all since this started, which is unusual The security system seems inactive too It is difficult to check the keyless entry, obviously I did check the fuses - visually they seem okay, but I haven't tested them with a multimeter Relays are a bit of a mystery to me - I wouldn't know where to begin with testing those Given your experience, does it sound like a deeper dive is needed or I am on the right track?

Thank you for the additional details From my recollection, the confluence of the car alarm, security system, and central locking failures certainly echoes my own experience Given your technical expertise, confirming the fuses with a multimeter would be worthwhile However, I acknowledge your apprehension regarding relay testing, as it can be a complex undertaking Considering the symptoms and your preliminary investigations, I must concede that a visit to a qualified workshop may be warranted While it is always prudent to explore DIY solutions, the intricate nature of modern vehicle electronics necessitates a degree of specialized knowledge and diagnostic equipment that may exceed the capabilities of the average enthusiast I'm not entirely certain this is the best advice, but that is what I would suggest

Appreciate the advice Took it to the workshop, and you were spot on – it was indeed a defective plug connection They charged me 95€, but at least it's sorted Thanks again for your help