I have a 2003 Ranger 4X4, 4.0 engine. Got in the truck today and the display on the radio (Mach MP3) shows "CALL." THe radio will not work, I've pressed each and every button on it to see if I can change it, but to no avail. I've called two dealerships and they both said they have no idea what it means and that they've never heard of such a thing. Can anyone help with this? Thank you in advance.