Where is the yellow card?

Hint 1 of 10:

The yellow card will open up the door to the escalators (right side).

Hint 2 of 10:

You would find it in one of the engines.

Hint 3 of 10:

Unfortunately, it's blocked off.

Hint 4 of 10:

There's an alternate way to get there though.

Hint 5 of 10:

Take the space train to the other side.

Hint 6 of 10:

Once there, look for three switches.