Inspection Procedure

1. Remove the navigation ECU with connectors still connected.
2. Check voltage.
   1. Measure voltage between terminals +B, ACC and GND1 of navigation ECU under each condition, as shown in Fig 1.
      Fig 1: Terminals +B, ACC and GND1 Continuity Specification Table - Navigation ECU

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      Voltage: 

      Fig 2: Identifying Terminals +B, ACC & GND1 Of Navigation ECU

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3. Check continuity.
   1. Check that the continuity exists between terminal GND1 of navigation ECU and body ground.

      Standard: Continuity exists. 

1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
2. OK: Go to next step. 

CHECK AND REPLACE NAVIGATION ECU