This morning, when I started the GX460, there for the first time, is a high pitched buzz. Cannot determine where is coming from and there are no trouble lights showing. Any Suggestions?

 

there is a high frequency sound when I first start my gx everytime. it only happens for about 10 seconds then goes away. i am not sure what it is, but it is probably normal. its hard to hear, but definitely there and mainly audible from outside the vehicle

 

Have you raised or lowered the third-row seats!? During operation and if they are not fully raised or fully lowered there is a high-pitched sound. To check, run both seats through a complete cycle, which will also make the sound. Was that what you heard?
Regards,

SaniDel

 

Believe someone mentioned this before. On the Premium model it may be the compressor kicking in for the air suspension system.

 

i listened more carefully.
it comes on about 10 seconds after starting the truck, and lasts a few seconds and then goes away. i assume its normal. engine sounds fine

 

You are correct, it was one of the third row seats that had not properly locked in place; thanks.