Inspection Procedure

1. Disconnect the DOME fuse from the engine room junction block.
2. Disconnect the ACC fuse from the driver side junction block.
3. Measure the resistance of the fuses.

   Standard resistance: Below 1 Ω 

NG : REPLACE FUSE 

OK : GO TO NEXT STEP 

1. Disconnect the N3 ECU connector.
2. Measure the voltage and resistance of the wire harness side connector.

   Standard voltage 

   TESTER CONNECTION AND SPECIFIED CONDITION CHART
   
   

   Tester Connection	Condition	Specified Condition
   N3-1 (+B) - Body ground	Always	10 to 14 V
   N3-13 (ACC) - Body ground	Power switch ON (ACC)	10 to 14 V

   Standard resistance 

   TESTER CONNECTION AND SPECIFIED CONDITION CHART
   
   

   Tester Connection	Specified Condition
   N3-15 (GND1) - Body ground	Below 1 Ω

   Fig 1: Checking Wire Harness (Navigation ECU - Battery And Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK : PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN  PROBLEM SYMPTOMS TABLE