8W-20 Charging System; Wiring Diagram Index - Jeep Wrangler 1997 Manual

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DESCRIPTION AND OPERATION
8W - 20 CHARGING SYSTEM
CHARGING SYSTEM
The charging system is an integral part of the bat-
tery and starting systems . Because all these systems
work in conjunction, diagnose and test them together.
Circuit All connects to the generator output termi-
nal and splices to the Power Distribution Center
(PDC). Circuit AO 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 Al from fuse 3 in
the PDC to circuit A21 . Circuit A21 feeds circuit F12
through fuse 11 in the fuse block. Circuit F12 splices
to supply current to the coil side of the Automatic
Shut Down (ASD) relay. The Powertrain Control
Module (PCM) provides ground for the relay on cir-
cuit 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 A14 from
fuse 6 in the PDC to circuit A142 . Circuit A142
splices to supply system voltage to cavity C12 of the
PCM. Circuit K72 from cavity C25 of the PCM sup-
plies current to the generator field terminal .
8W-20 CHARGING SYSTEM
SCHEMATICS AND DIAGRAMS
8W - 20 - 1
The PCM has an internal voltage regulator that
controls generator output. The PCM controls the gen-
erator 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+ volt-
age. The generator supplies B+ voltage to the battery
through the All and AO circuits .
HELPFUL INFORMATION
" Circuit F12 also powers the coil side of the fuel
pump relay and A/C compressor clutch relay.
" The ASD relay supplies battery voltage for the
fuel injectors, ignition coil, and heated oxygen sen-
sors.
WIRING DIAGRAM INDEX
The following index covers all components found in
this section of the wiring diagrams . If the component
you are looking for is not found here, refer to section
8W-02 for a complete list of all components shown in
the wiring diagrams .