Circuit Operation

CIRCUIT OPERATION
The charging system is an integral part of the battery and starting systems. Because all these systems work in conjunction, diagnose and test them together.

Circuit A11 connects to the generator output terminal and the Power Distribution Center (PDC). Circuit A0 connects the battery to the PDC. Circuit ZO provides ground for the generator.

When the ignition switch is in either the START or RUN positions, it connects circuit A1 from fuse 2 in the PDC to circuit A21. Circuit A21 splices to circuit F12 and supplies current to the coil side of the Automatic Shut Down (ASD) relay The Powertrain Control Module (PCM) provides ground for the relay on circuit K51. Circuit K51 connects to cavity C3 of the PCM.

When the PCM grounds the ASD relay, contacts inside the relay close and connect circuit A16 from fuse 18 in the PDC to circuit A142. Circuit A142 connects to cavity C12 of the PCM.

The PCM has an internal voltage regulator that controls generator output. The PCM controls the generator field on circuit K20. Circuit K20 connects to PCM cavity B10.

When the engine operates and there is current in the generator field, the generator produces a B+ voltage. The generator supplies B+ voltage to the battery through the A11 and A0 circuits.