After reading numerous posts on the radio code for a 1998 4.6 HSE, I learned that holding down the band button for 10 seconds allows you to enter the radio code following a battery disconnection. it worked perfectly, code accepted, radio on. So far, so good. But, 10 minutes later the LCD died, and the speakers started emitted a buzzing, no radio/sound functions work other than on/off. I cannot get the code in back. What do I do please?