Ignition Switch: Description and Operation

When the ignition switch is in the START/RUN position, it connects circuit A1, from the fusible link near the auxiliary jumper post, to circuit A21 through the ignition switch. Circuit A21 connects from the ignition switch to fuse 8, a 5 amp, in the fuse block. At the fuse, circuit A21 is double crimped and supplies power to a splice that powers the EVAP/purge solenoid, Automatic Shut Down (ASD) relay, radiator fan relay, Ignition Control Module (ICM), and the data link connector.

At the data link connector the A21 circuit is double crimped and connects to the Powertrain Control Module (PCM). This input to the PCM indicates when the operator is starting the vehicle.