GLA hybrid transmission issue

I had similar transmission issues with my GLA. The temperature sensor error is a pain. Gear shifting became erratic, almost unpredictable. Have you checked the basics, like the transmission fluid level That was the culprit in my case. I remember thinking it was going to be a major transmission repair, but thankfully, it was relatively straightforward.

Thanks for sharing your experience. When you checked the transmission fluid level, was it visibly low or did you rely on a diagnostic tool to determine that Also, did the issue resolve immediately after addressing the fluid level, or were there any lingering symptoms that required further attention

I didn't have the tools to properly check it myself, so I took it to a workshop. They confirmed the low level and topped it off. That fixed the slipping and rough shifting, but the error code related to the transmission sensor persisted for a bit. It eventually cleared itself after a few drive cycles. Honestly, given your symptoms, I'd recommend getting it checked out by a professional. Could save you a lot of headaches in the long run.

I appreciate your advice. It seems prudent to consult with a qualified technician, given the complexities involved. I took your advice and after visiting the workshop, the root cause was indeed the faulty transmission oil temperature sensor. The sensor was replaced, resolving all the symptoms. The total expenditure amounted to 365€.