ECM Power Source Circuit Check

When ignition switch is turned on, battery positive voltage is applied to ignition coil, closing contacts in EFI main relay and supplying power to terminals +B and +B1 of ECM.

Fig 1: ECM Power Source Circuit Check - Schematic

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Fig 2: ECM Power Source Circuit Check - Diagnostic Flowchart (1 Of 3)

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Fig 3: ECM Power Source Circuit Check - Diagnostic Flowchart (2 Of 3)

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Fig 4: ECM Power Source Circuit Check - Diagnostic Flowchart (2 Of 3)

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