Dont have a clue on what happened, last night while driving my mark LT,
nav unit suddenly went black, couldnt change radio station on it,
no more steering wheel control, no cd playing....
Only thing still working is volume on unit.
Anyone had this issue or knows what's happening ?
Thanks

 

This may or may not be helpful, but I figure it can not hurt. I have a pioneer avic navigation unit that stopped working and locked up showing a black screen. The hard drive was dead. I removed the hard drive, which allowed me to use the fm radio until I bought a replacement hard drive. Once I put the new hard drive in everything worked perfectly.