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

Relay Locations:

The Auto Shut Down (ASD) Relay controls power to the ignition coil, fuel injectors, and electric fuel pump. Controlled by the Single Module Engine Controller, (SMEC) the ASD supplies power to the ignition coil, fuel injectors, and electric fuel pump at all times when the ignition switch is in the START position. When the ignition switch is in the RUN position and the SMEC is receiving a reference signal from the distributor, power will also be supplied. But if there is no reference signal after two seconds the SMEC will de-energize the ASD and no power will be supplied to the ignition coil, fuel injectors, or electric fuel pump.