Looking at this diagram (Thanks Rekcah) it shows the module either blows or sucks all three at the same time so if when testing it, all three should do the same thing. Looks like a module not doing what its supposed to (to me). Search for a less expensive one they are out there.

One last thing! Did you try hitting the lock/unlock button twice? I understand (from somewhere deep down in my grey matter) that you can set it up to lock/unlock in stages. Anyone else remember this or have a different take on this?