Check And Replace Ecu

First check the ECU ground circuit. If it is faulty, repair it. If it is normal, the ECU could be faulty, so replace the ECU with a normal functioning one and check that the symptoms appear.

1. Measure the resistance between the ECU ground terminal and the body ground.

   Resistance: 1 Ω. or less 

   Fig 1: Measuring Resistance Between ECU Ground Terminal And Body Ground

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2. Disconnect the ECU connector, check the ground terminals on the ECU side and the wire harness side for bend and check the contact pressure.
   Fig 2: Checking Ground Terminals On ECU Side And Wire Harness Side

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