S Klasse Hybrid Overheating and Coolant Leak

This sounds familiar. I had a similar issue with my S Klasse. It turned out to be a wiring problem disrupting the data link to a control unit. The car was receiving incorrect data and overcompensating, leading to odd behavior. Begin by inspecting your cable or plug connections. It could also be a faulty sensor. Is the coolant leak near the engine? That might help narrow it down.

When you mention a wiring issue, are you referring to a specific wire or a general connection problem? I'm not very technical, so any guidance on where to start looking would be great. And yes, the coolant seems to be leaking from the front of the engine.

In my case, it was the plug connection. The bad data link was also causing my engine to overheat. I'd recommend having a shop check the data link to the control unit. A faulty cable or plug connection is the most likely cause. If the coolant is leaking from the front of the engine, there's probably a coolant line nearby. However, I'd definitely have a professional examine it, because continued pressure buildup could lead to a more costly problem.

I took it to the shop, and you were right! It turned out to be a faulty plug connection on one of the engine sensors. It was disrupting the entire system, causing the overheating and coolant issues. 95€ later, it's all fixed. Thanks for the help!