Corolla hybrid belt handover issue

Have you considered the possibility of a defective belt handover itself? I encountered a comparable predicament with my 2018 Opel Insignia, albeit a different make. The symptoms you describe bear a striking resemblance to the issues I faced, which eventually led to the replacement of the tensioner assembly.

You mentioned it might be the belt handover itself. How did you determine that was the issue? Was it making any specific noises or showing any other signs before you replaced the tensioner assembly?

The diagnosis was multifaceted, involving a careful examination of the belt's alignment, tension, and overall condition. Moreover, the presence of unusual wear patterns and the absence of the expected tactile feedback during belt engagement suggested a compromised handover mechanism. Considering the intricate nature of the system, I would strongly advise seeking professional evaluation to ascertain the root cause. Perhaps a visit to a qualified workshop is in order?

Thanks for the advice. I took it to the shop, and you were right! It was indeed a defective belt tensioner; they replaced it, and the handover works perfectly now. The repair cost me 455€. Appreciate the insight!