DTC 58-42: Map Disc Read Error; DTC 80-42: Map Disc Read Error: Procedure

1. Check that the map disc is not deformed or cracked.
   Fig 1: Identifying Deformed Or Cracked Disc Condition

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK

   No deformations or cracks on the map disc.

NG → See step   4 

OK: Go to next step 

1. Disc cleaning
   Fig 2: Cleaning Disc With Soft Cloth

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. If dirt is on the disc surface, wipe it clean with a soft cloth from the inside to the outside in a radial direction.
      NOTE:

      Do not use a conventional record cleaner or anti-static preservative.

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Recheck for DTCs and check if the same trouble occurs again.

   OK

   Same problem does not occur.

OK → END 

NG: Go to next step 

1. Replace the map disc.
2. Clear the DTCs and recheck for DTCs.
3. Check if the same trouble occurs again.

   OK

   Same problem does not occur.

OK → END 

NG → REPLACE NAVIGATION ECU