Dakota 4WD V6-239 3.9L VIN X FI (1989)
Automatic Shut Down (ASD) Relay: Description and Operation
Relay Identification
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 reference signals 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.
