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Power Circuits

To test Powertrain Control Module (PCM) power circuits, see Fig 1 or Fig 2 . After completing the tests, retest the vehicle to ensure the faults have been rectified. If faults still persist, recheck using Lucas diagnostic equipment.

Fig 1: Engine Control Module Power Circuits Test Procedure No. 1 & 2 (1987-88)
G00066885Courtesy of LAND ROVER NORTH AMERICA, INC.
Fig 2: Engine Control Module Power Circuits Test Procedure No. 1 & 2 (1989-91)
G00066931Courtesy of LAND ROVER NORTH AMERICA, INC.