Lexus navigation system - disc read error?

Try cleaning your disc with CD cleaner. Depending on how old your car is, the laser lens may have dust on it, thus inhibiting its ability to read. With the Infinity systems in Dodges, we call it the BKBW fix - butter knife and baby wipe. Literally take a butter knife and wrap a baby wipe over it. then slide it into the slot and gently work it around, then pull out. Might not work on a Lexus but definitely helps on some others. Good luck.