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Power & Ground Circuits

  1. Ensure ignition is off. Using a DVOM, measure resistance between ECU terminal No. 22 of connector E11 and ground with ECU connector connected. See Fig 1.
  2. Resistance should be one ohm or less. If resistance is within specification, replace ECU with a known good unit and check if symptoms reappear. If resistance is not within specification, carefully disconnect ECU connector.
  3. Check ECU ground terminal and wire harness connector for damage. Repair as necessary. If ECU ground terminal and wire harness connector are okay, replace ECU.
Fig 1: Identifying LS400 ECU Terminals
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