Main Relay (Computer/Fuel System): Description and Operation
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Location
The ASD relay is housed in the [1][2]Power Module.
Purpose
The Logic Module controls the ignition coil, fuel pump, fuel injector, and [1][2]power module, through the ASD relay, by grounding the relay.
Operation
The Logic Module monitiors the distributor pick-up signal, and if the Logic Module senses this signal (engine is running), the logic module grounds the ASD relay.
If the Logic Module does not sense a distributor pick-up signal, the logic module removes the ASD relay ground (within one second), interrupting power to the fuel pump, fuel injector, and ignition coil.
This "Shutdown" is intended to stop fuel flow and ignition spark in the event of an accident.