ECU Power Source Circuit: Procedure

1. Measure the voltage according to the value(s) in the table below.
   Fig 1: >Identifying Terminals Of A9 Active Control Engine

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   Standard voltage

   Tester Connection	Condition	Specified Value
   +B (A9-2)- Body ground	Always	10 to 14 V
   IG2 (A9-10) - GND (A9-12)	Engine switch on (IG)	10 to 14 V

OK → CHECK FOR INTERMITTENT PROBLEMS 

NG: Go to next step 

1. Disconnect the active control engine mount ECU connector.
   Fig 2: Identifying A9 Active Control Engine Mount ECU Connector Terminal

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

   Standard resistance

   Tester Connection	Specified Condition
   GND (A9-12) - Body ground	Below 1 Ω

3. Reconnect the active control engine mount ECU connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ACTIVE CONTROL ENGINE MOUNT ECU - BODY GROUND) 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (ACTIVE CONTROL ENGINE MOUNT ECU - BATTERY)