Navigation ECU Power Source Circuit: Procedure

1. Disconnect the navigation ECU connector.
   Fig 1: Identifying Z22 Navigation ECU 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
   z22-15 (GND1) - Body ground	Always	Below 1 Ω

3. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Condition	Specified Condition
   z22-1 (+B) - z22-15 (GND1)	Always	10 to 14 V
   z22-13 (ACC) - z22-15 (GND1)	Power switch on (ACC)	10 to 14 V

NG → See step   2 

OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE 

1. Disconnect the multi-display connector.
   Fig 2: Identifying H1 Multi-Display Connector

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2. Measure the resistance according to the value(s) in the table below.
   Fig 3: Identifying Z22 Navigation ECU Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Condition	Specified Condition
   h1-6 (GND) - z22-15 (GND1)	Always	Below 1 Ω
   h1-7 (ADET) - z22-13 (ACC)	Always	Below 1 Ω
   h1-8 (+B) - z22-1 (+B)	Always	Below 1 Ω
   h1-6 (GND) - Body ground	Always	10 kΩ or higher
   h1-7 (ADET) - Body ground	Always	10 kΩ or higher
   h1-8 (+B) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE MULTI-DISPLAY