Toyota Tundra Service Manual > Navigation System: Sound Quality is Bad Only when Disc is Played (Volume is Too Low)
PROCEDURE 1. REPLACE DISC WITH ANOTHER AND RECHECK (a) Replace the disc with a known good one and check that the malfunction disappears. OK: Malfunction disappears. Result Result Proceed to OK A NG (for Column Shift Type) B NG (for Floor Shift Type) C A END (DISC IS DEFECTIVE) B REPLACE NAVIGATION R ...