I have a 2002 Jeep Liberty that displayed something that looked like an EKG on the display when the system was off. When I turned the system on, the tuner located a station and displayed the current play list but the volume control does not work and there is no sound. CD changer and tape also work but no sound. I checked fuse but all appeared OK. Any thoughts on what the problem could be?
Is there a “mute” function? Has someone accidentally activated it?
Are you sure it doesn’t say Err? Your manual will tell you what’s up when you get an “err” display. Maybe simply removing the battery cable and reconnecting it will reboot the radio. Either way I believe your manual should tell you what to do. If it is EKG, I don’t have a clue what that would be? Engine Kill Guard? Not related to the radio.
Is this a stock or aftermarket radio? Is there an external amplifier?
If it’s a stock radio, it’s probably done for. The good news is that it’s cheap and easy to get a replacement from someplace like Crutchfield www.crutchfield.com
If it’s aftermarket, does it have a removable faceplate that might be loose and therefore the controls are doing odd things? Easy to check and fix, if that’s the problem.
Finally, if there is an external amplifier, it may have a separate fuse of its own either on the amp or inline in the power feed.
Hope this helps.