not a kata issue :-)

Very nice kata.

One thing I spotted is your check for to many doors.
One door only takes two spaces, not three as in your solution.

Second problem is the space character, you try to set the empty spaces to the ASCII 32 character,
but because chars aren't reference types the values in the array are not changed.
If you set every character in 'secondLayerChar' to a space right at the beginning, your solution works.

One other hint, you can use string::repeat instead of for loops.

messed up printing

The printing are done after the test statement, which is pretty confusing IMO (usually they're put before the actual print statement).

Description updated / approved

Nice funny one! Quite hard to rank... (6,5 would be nice... ;) )

Some suggestions of things to add to the description:

• You should establish what type of exception you want (unchecked or checked). Maybe even the exact type of exception? (runtime? illegalArgument?)
• You forgot to explain that a trailing/leading "\n" has to be added either in the middle part or the bottom part (same for the two upper parts, but there it is more evident).
• It's implicit, but IMO you should say it loud: component, Body, Chassis, Car.body and Car.chassis have to be public

Note: You surely noticed at what I said that I talk about Java. I don't know JS, so might be that some of my suggestions need some adjustments...

In any case, I liked it, really! :)

Cheers!