While testing is only mentioned in the book, it is a critical element of production to catch assembly errors as soon as possible. As very expensive systems are assembled, the further down the process the mistakes go, the harder and more expensive they are to correct.

After assembly, the boards are placed on a "bed of nails" tester that has "pogo pins" which touch critical test points in the circuits, and the board is quickly powered up and runs a few basic tests to see if everything is there.