Yep, tried Aux 2. Off and then on. Still flickers.
The flickering headlight usually means the engine is receiving a weak TMCC signal.
If you have other TMCC engines that are working O.K. this new to you engine may have an antenna problem. On the steam engines the handrails along the boiler are usually used as the antenna. Yours may be loose and not making a good connection inside the engine. Other threads and topics on this forum have addressed this weak signal issue.
Good luck with your engine.
Mark
Oops...I see you have been having these problems with another engine covered in another thread. Sorry to have repeated what has been already posted.
Mark