Took apart the steering wheel, left foot kick panel, and the knee panel to inspect wiring.
While I may have found the problem per the FSM... I'm not convinced it's accurate.
I've had a lot of Toyotas and have found, at times, the FSM is written by people and as such, aren't always accurate. One of the wire tests "failed" and the result is to replace wiring. While possible that's accurate, absolutely nothing else is wrong with the vehicle nor any steering wheel functions/buttons.
Now here's what/why I believe the problem lies elsewhere...
The FSM, for my situation, tells you to pull the cable from the controller and test the wire you pulled for resistance values. If failed, replace the controller.
Only problem is the resistance test, which passed, does not test the controller but the heater end itself.
Later, after pulling the wheel apart (requiring the battery be disconnected) the FSM tells you to check for voltage.
I'm going with my gut and have ordered (used) a heater controller. If that's not it I'm out very little and wrong, but no worse off than I am now.
