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Power Circuits

  1. Ensure ignition is off. Use DVOM to check for constant battery voltage at pin No. 18 (Red wire). Battery voltage should also be present at pin No. 36 (Brown wire). Pin No. 36 is power feed from main relay. Computer will ground Pin No. 36 to activate main relay during cranking and running operation.
  2. Turn ignition on. Battery voltage should be present at pin No. 37 (Red/Blue wire). During cranking, battery voltage should be present at pin No. 27 (Green wire). See WIRING DIAGRAMS article for more information.
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