Page L-1
Repair and Service Manual
ELECTRICAL
Read all of Section B and this section before attempting any procedure. Pay particular attention to all Notes, Cautions and Warnings.
CIRCUITS AND CONTROLS
The electrical system is a 12 volt negative ground sys-
tem (Ref. Fig. 1 on Page L-2) (Ref. Fig. 2 on Page L-3)
consisting of a:
•
battery
•
starter/generator
•
voltage regulator
•
solenoid
•
ignitor
•
ignition coil
•
accelerator limit switch
•
fuse
•
key switch
•
pulser coil
To prevent injury or death from inadvertent
movement of vehicle, all tests performed
requiring starter/generator or engine to rotate
must be performed with the rear wheels raised
(see Section “B”) or the neutral lock engaged
(see Section “A”).
Follow the lifting procedure in Section “B” of
this manual. Place wheel chocks in front of
and behind the front wheels. Check the stabili-
ty of the vehicle on the jack stands before
starting any repair procedure. Never work on a
vehicle that is supported by a jack alone.
STARTER
When starting the engine, the field coils are in series
with the armature and the starter/generator operates as
a motor (Ref. Fig. 1 on Page L-2). This circuit is con-
trolled by a key switch, fuse, accelerator limit switch and
a solenoid. With the key in the
‘ON’
position, battery
current is available to the accelerator limit switch which
remains open until the accelerator pedal is pressed.
When the pedal is pressed, the plunger on the switch is
released, the contacts close and the ignition circuit is
energized. Battery current then energizes the solenoid
which closes the contacts and energizes the starter cir-
cuit. The starter/generator now functions as a starter to
start the engine.
GENERATOR
When the engine is running, the starter/generator func-
tions as a generator. This is used for charging the bat-
tery and for the ignition system. Generated output is
controlled by the voltage regulator at 14.25 - 14.75 V,
without regard to engine speed. However, the charging
current will vary depending on the condition of the bat-
tery. If it is fully charged, current is controlled at 3 to 5
amps.
WIRING
Before performing any test of wiring compo-
nents, disconnect the battery cables from the
battery posts to prevent electrical shock or
explosion (see procedure in Section “B”).
Electrical tests of the wiring for continuity may be made
with a DVOM (Digital Volt Ohm Meter) available through
the Service Parts Department (P/N 27481-G01). Any
DVOM may be used, however the controls, displays
and features may vary depending on the make and
model. Set the meter selector to the ohms scale and
check continuity between each circuit component as
indicated. Example: If a switch is open or if there is a
break in the wiring, the meter will display a visual signal.
If an analog meter is used it will read infinity (
∞
).
TESTING IGNITION CIRCUIT
This section assumes the fuel system is functioning and that
the engine is receiving fuel.
Tool List
Qty. Required
DVOM.......................................................................... 1
Spark plug (NGK BPR4ES) ......................................... 1
Spark plug tester ......................................................... 1
To prevent possibility of personal injury, never
operate the starter unless both spark plugs are
installed or the ignition system is disabled.
Fuel drawn into the cylinders will be expelled
through the spark plug opening and could be
ignited by the ignition system or another
source, resulting in a fire.
The engine incorporates a solid state ignition system
that fires both plugs simultaneously. There is no distrib-
utor.
The engine can be stopped by turning the key switch to
the
‘OFF’
position. When the accelerator pedal is
released, the limit switch contacts open and the ignition
circuit is de-energized.
