I've noticed that the TL buses have white buttons with a pram sign on them at the doorways. I assumed they were to lower the floor at the bus stops. Does pressing these buttons have any effect? So far I've not noticed anything on the old buses (I only use the part of the bus with no steps), and I would say maybe on the newer buses the floor is lowered if the driver sees you.
Can someone tell me how and if these buttons actually work, or whether relying on the Lausannois population is my best bet for getting baby safely off the bus.

I believe it is to ensure that both doors open instead of just one.

and i think they may stay open a bit longer, but i'll experiment on that tomorrow morning and let you know

Yes. The pram button keeps the doors open longer.

Thanks all....disappointed to hear that though - was really hoping they were there for lowering the floor.

Not sure where you live, but here in zurich the floor thing is up to the driver in the new buses (the old ones has steps) I try to make sure to outstand in the crowd so the driver notice i will be getting in with the ginormus stroller and generally they lower the floor for me (or whatever number of strollers getting in)

Just how high is the floor for you to be so disappointed?!?

My experience is that the new buses have lowered floors anyway, so lowering them makes no difference, while buses/entries with steps don't benefit from floor lowering anyway...

I always imagined that the blue pram button released a cacophony of invective, to save the locals the effort.

The normal door button causes the door to open and then close again automatically after a certain time.

When opened with the pram button, the door does not close automatically but the driver has to close it by pressing a special close button. Presumably he or she should check first that the pram is safely on or off (by way of the mirror or CCTV).

If there is nobody else around the driver may (should?) also offer to help.

Enough that sometimes it's like I'm emptying a wheelbarrow!