My compressor wentsoulsea said:Take it to an auto parts store where they can read the code. But make sure they don't erase the code afterwards cause you might need the dealer to read it to if it's something serious. It could be related to the service suspension warning or it could be something completely different, without an audio clip it's going to be difficult here for someone to diagnose it.
I had a whining sound from my engine on my previous Escalade and it turned out to be a faulty water/coolant pump. It could also be a steering pump, or it could be one of a number of other things. Like I said, it'll be easier to tell if you could post a youtube clip of the sound.