Sound Signal Circuit between Navigation ECU and Multi-media Interface ECU: Procedure

1. Disconnect the display and navigation module display connector and the multi-media interface ECU connector.
   Fig 1: Display And Navigation Module Display Connector

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2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G23-1 (AGND) - U9-1 (USD1)	Always	Below 1 Ω
   G23-3 (VAR+) - U9-2 (URO+)	Always	Below 1 Ω
   G23-4 (VAL+) - U9-3 (ULO+)	Always	Below 1 Ω
   G23-7 (VA-) - U9-4 (UGD1)	Always	Below 1 Ω
   G23-1 (AGND) - Body ground	Always	10 kΩ or higher
   G23-3 (VAR+) - Body ground	Always	10 kΩ or higher
   G23-4 (VAL+) - Body ground	Always	10 kΩ or higher
   G23-7 (VA-) - Body ground	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Display and Navigation Module Display)
   *2	Front view of wire harness connector (to Multi-media Interface ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   2