2008 G35x recently purchased w/168,000 miles

Driver seat w/ memory. The forward and back function is not working. It worked intermittently upon purchase a couple months ago, but has now stopped functioning altogether. All other functions work well (recline, front edge lift, lumbar inflation).

-I identified the correct motor and removed it from under the seat expecting it to be bad. However, I tested it with direct 12v current from the battery and it operated well...including rotating both directions as I swapped contacts. I then reconnected the motor to the harness under the seat and no function...so somehow no current getting to the harness.

-I then suspected the switch, however I am hearing a definite "click" from under the seat each time I slide the switch (both forward and back). This "click" sounds to be coming from the white rectangular electrical box mounted under the seat. I believe that is the memory module? (The same "click" is present for the other properly working functions when activated.) The "click" sounds much like a relay being activated, which leads me to believe that current is indeed getting through the switch...which leads me to believe the switch is not bad. But I could be wrong. Suggestions on testing the switch?

-Assuming I am correct that both the switch and motor are not bad, what else could it be? I think the only other component in the chain is the white box. Thoughts?

Much thanks from a G35 newbie!