This is really something about which I am curious as opposed to a problem. Sometimes when I start my 350h luxury, I get a chime sound. Sometimes I don’t. I assume it has something to do with the hybrid system, but don’t understand the inconsistency.

Any insight is appreciated.

Update. When my wife rode with me the other day I realized the chime sound I heard when she unbuckled her seat belt was the same sound I was hearing when I started the vehicle. So it’s as simple as sometimes I buckle my seat belt before I start the vehicle and sometimes I do not.