97 Explorer Sport - electronic whine

[JDegenerate]

I recently picked up a 1997 Explorer Sport and it's making a quiet, high pitched electronic whine, even while the car is off. It seems to be coming from the radio, though I'm not certain. Most of the time, when I turn the electronics on, the whine picks up into a loud noise that randomly changes tone. Taking the key out, then turning the electronics on again typically makes it go back to the quiet, high whine. Using any other electronics such as window buttons makes the tone change. I plan on changing the stereo unit out anyway, but I'd like to know what else to look out for anything else in case that's not the source.

Thanks!

 

[J_C]

Radio would be my guess. You could pull the fuse to it to see if that stops it.

If there's anything else on that fuse that you need working so you can't leave it out, even if you don't have a new radio yet, I'd pull the old one and unplug it if it is causing any excessive battery drain as something like this could drain your battery, and get worse then drain it worse.

The only other thing I can think of would be if one of the relays has a whiny coil in it. You could pull them one by one to check, after ruling out the radio. Considering when it's making the noise I would sooner suspect the battery saver or light relay.

 

[vroomzoomboom]

check your body grounds and make sure they are in good shape.