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Distributor Reference Signal

PURPOSE
The distributor reference signal provides the control module with both engine RPM and crankshaft position information. This enables the control module to operate the fuel pump relay and energize the fuel injector.

OPERATION
When the engine is cranking or running the control module receives Distributor Ignition (DI) reference pulses from the ignition module. If the wire becomes open or grounded the engine will not run, as the control module will not operate the injector.