Main Relay (Computer/Fuel System): Description and Operation

NOTE: The following information is intended to be used in conjunction with the electrical diagrams.

CIRCUIT OPERATION
Circuit A14 from the Power Distribution Center (PDC) supplies battery voltage to the contact side of the Automatic Shut Down (ASD) relay.

Circuit A21 from fuse 14 in the fuse block supplies battery voltage to the coil side of the ASD relay. The Powertrain Control Module (PCM) provides the ground path for the coil side of the relay on circuit K51. Circuit K51 connects to cavity 51 of the PCM connector.

Circuit A142 splices to supply voltage to the fuel injectors, ignition coil, and heated oxygen sensor. Circuit A142 also splices to cavity 57 of the PCM. This input tells the PCM that the ASD relay has energized.