ervwalter

Thanks all. Glad to know that it is a typical occurance and not something happening to just me.

When I press my foot on the brake pedal and before I press the "start" button, a high pitch tone starts from under the hood of my 2011 MKX (premium/elite package if that matters). It sounds electronic (i.e. not something mechanical rubbing on something else). It isn't especially loud. Although the vehicle drives fine and there are no other symptoms, I wondered if it was a symptom of something that was wrong or failing. As far as I can tell, the tone doesn't stop when the engine starts, but it is much harder to hear over the engine noise. I don't know if it stops at some point after the engine has been running for a while. The technician at the dealer obviously had never heard of it before but said he didn't think it was abnormal. Given that he wasn't ware of it as a normal behavior prior to me asking about it, I am not sure how he came to the conclusion that it was not abnormal. Does anyone know if this is a normal behavior and just indicates that something is getting energized/primed prior to me starting the engine?