MEX airport trains between terminals 1 and 2

Someone reported that at the Mexico City International Airport (MEX) the trains between terminals weren’t operational last month. Can anyone say whether they’re back up and running?

Yes the plane train is up and running. We were on board the week after Christmas. With that being said the transition between terminals can be a hassle. Especially when immigration is involved. A long layover helps or better yet the direct flight to Zih when available