Mercedes GT Roadster Transmission Problems

That sounds frustrating. The implausible shifting, warning light, and emergency mode all point to a serious problem. You mention worn transmission oil. Have you checked the fluid level and condition? Is it low, or does it appear dark and burnt? Also, you mentioned a transmission flush, but have you considered that low voltage in the vehicle could be the root cause of the problem, especially with a hybrid?

Thanks for the quick response. I haven't checked the transmission fluid level myself yet, honestly. Where exactly would I check that on this model? And regarding the low voltage, what exactly would cause that, and how would that even affect the automatic transmission? I'm not really sure where to start looking for that.

Checking the transmission fluid level can be tricky on some modern automatics; you might need special tools or knowledge. As for the low voltage, hybrids have complex electrical systems. A weak battery, faulty alternator, or even a bad ground connection can cause undervoltage situations. The car's computer might interpret this as a transmission fault, triggering the emergency mode. Given the symptoms and complexity, I'd suggest having a qualified mechanic diagnose it properly. It is better to be safe than sorry.

Thanks for the advice. I took it to a local independent shop, and you were spot on. It turned out to be undervoltage causing the transmission issues. They checked everything out, reset the system, and replaced the transmission oil as a precaution. Total cost was around 240€. Shifts like new now.