Inspection Procedure

CHECK CABIN
1. Check the cabin for any object that might interrupt radio reception on the instrument panel. If such an object exists, remove it and check if the GPS mark reappears.
  HINT:
  
  The GPS uses extremely faint radio waves originating from satellites. If the signal is interrupted by obstructions or other radio waves, the GPS may not be able to properly receive the signal.
  
  OK: The GPS mark appears .
  
  NG: Go to step 2
  
  OK: NORMAL OPERATION
CHECK SURROUNDINGS
1. Check if the vehicle is in a location where GPS signal reception is poor. If the vehicle is in such a place, relocate the vehicle and check if the GPS mark reappears.
  HINT:
  
  The GPS uses 24 satellites in 6 orbits. At any point in time, 4 satellites should be able to pinpoint your vehicle. However, GPS signals may not reach the vehicle due to influence from the surroundings, vehicle direction, and time. For examples, see the following illustration.
  
  Fig 1: Vehicle Surroundings Checking Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  OK: The GPS mark is displayed .
  
  NG: Go to step 3
  
  OK: SYSTEM RETURNS TO NORMAL
CHECK GPS INFORMATION (NAVIGATION CHECK MODE)
1. Enter the "Navigation Check" mode (GPS Information) (See OPERATION CHECK ).
2. Check how many of the following codes appear in the "STS" column.
  for DENSO Made: T, P
  
  for AISIN AW Made: 08H, 04H
  
  Fig 2: Identifying GPS Information
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  OK: At least 3 codes appear .
  
  NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (See PROBLEM SYMPTOMS TABLE )
  
  OK: REPLACE NAVIGATION RECEIVER ASSEMBLY (See REMOVAL )