Much to my surprise, the AUX jack in my wife's Lexus is well-hidden in a secret compartment within the center consol. She has had the car for over a decade, and I never knew that there was an AUX jack (never needed it). However, the Hamilton system requires the use of the AUX jack to operate properly (this I found out after a few calls with Hamilton tech support). Attached are some photos showing where the jack is located...hope this helps.
