DTC P16A3: TACH Signal Communication: Procedure

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

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2. Measure the voltage between the TACH terminal of the A9 Active control engine mount ECU connector and body ground.

   Standard

   Tester Connection	Specified Value
   TACH (A9-16) - Body ground	Correct waveform is as shown

OK → REPLACE ACTIVE CONTROL ENGINE MOUNT ECU 

NG: Go to next step 

1. Disconnect the A9 active control engine mount (ACM) ECU connector and A10 ECM connector.
   Fig 2: Identifying ACM ECU Connector Terminals & ECM Connector Terminals

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

   Standard resistance

   Tester Connection	Specified Value
   TACH (A9-16) - TACH (A10-15)	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE ECM