Regulator; Charging System Application - Ford LSG 875 Service Manual

4-03 CHARGING 4-03
DESCRIPTION AND OPERATION (Continued)
.
A 500 ohm, l/4 watt resistor is connected across warning lamp or through terminal S on vehicles
the terminals of the lamp at the instrument cluster equipped with an ammeter. With an input voltage
in vehicles equipped with an indicator warning present, the switching circuit turns on the voltage
lamp.
control circuit, which in turn controls the output
The switching circuit receives voltage from the
ignition switch through the warning lamp control
circuit on vehicles equipped with an indicator
circuit. When the ignition switch is Off, the output
circuit remains open and no current flows to the
alternator field.
REGULATOR
The electrical charging systems incorporate a
new electronic voltage regulator. These reg-
ulators are 100 percent solid state, consisting of
transistors, diodes, and resistors. The working
functions are achieved using electronic compo-
nents arranged in basically three circuit divisions
as follows: the output stage, the voltage stage,
and the solid state relay.
The new regulator will be released under two
separate part numbers with color codes. The units
will look alike, but are not interchangeable with the
new regulator wiring harness connector plugs.
One of these units will be used on vehicles
equipped with an ammeter, the other on vehicles
equipped with an alternator warning indicator
lamp. The regulators are calibrated and preset by
the manufacturer. No readjustment is required or
possible on these units.
The new solid state regulators being used in
conjunction with other new components in the
charging system that must be properly matched to
prevent damage to the charging system are as
follows:
1. A new alternator with higher field current
requirement.
2. A new warning indicator lamp shunt resistor.
3. The alternator to regulator wiring harness is
changed to incorporate a new regulator con-
nector plug. The new plug is designed so that
the connector will not index with the regulator
terminals when the wrong regulator is inad-
vertently installed in the vehicle.
TO AMMETER AND
GNITION SWITCH
t ALTERNATOR
#
I
FI FPTPnhllP
STAT+%?
STARTER MOTOR
RELAY
K4927.2E
TO 500 OHM RESISTOR
AND INDICATOR LAMP
A
ALTERNATOR
APPLICATION
Whenever the system components are being
replaced, the following precautions should be fol-
lowed so that the charging system will work prop-
erly and components will not be damaged.
1. Always use the proper alternator in the sys-
tem being serviced. Older model alternators, if
used in the present system, will have a slightly
reduced output.
2. Never use an electro-mechanical regulator in
the new charging system. The connector plug
on the new system wiring harness will not
index properly with the electro-mechanical
regulator.
3. The electronic regulators are color coded for
proper installation. Always use the black color
coded regulator in systems which use the
warning lamp indicator. The blue color coded
regulators must be used in ammeter gauge
systems.
4. The charging system uses a 500 ohm resistor
on the back of the instrument cluster on units
with a warning indicator lamp. Do not replace
this item with the 15 ohm resistance wire.