Read all of SAFETY and this section before attempting any procedure. Pay particular attention to Notices, Cautions, Warnings and Dangers.
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Repair and Service Manual
699322
ELECTRICAL SYSTEM
The electrical system is a 12 volt negative ground system
(Ref. Fig. 1) consisting of a:
•
Battery
•
Starter/generator
•
Voltage regulator
•
Solenoid
•
Fuse
•
Key switch
To prevent injury or death from
inadvertent movement of vehicle,
all tests performed requiring
starter/generator or engine to rotate must be per-
formed with the rear wheels raised (see the SAFETY
section) or the neutral lock engaged (see the Gen-
eral Information and Routine Maintenance section).
Follow the lifting procedure in the SAFETY section
and the General Information and Routine Mainte-
nance section of this manual. Place wheel chocks
in front of and behind the front wheels. Check the
stability 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). This circuit is controlled 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 circuit. 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 battery
and for the ignition system. Generated output is con-
trolled 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 battery. If it is
fully charged, current is controlled at 3 to 5 amps.
WIRING
Before performing any test of wir-
ing components, disconnect the
battery cables from the battery
posts to prevent electrical shock or explosion.
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 27481G01). 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 con-
tinuity 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
NOTICE: This section assumes the fuel system is
functioning and that the engine is receiving fuel.
Tool List
Qty.
DVOM.......................................................................... 1
Spark plug (NGK BPR2ES)......................................... 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 an induction type ignition sys-
tem driven by the ECM.
The engine can be stopped by turning the key switch to
the
OFF
position. When the accelerator pedal is
released, the second limit switch contacts close, signal-
ing the ECM to deactivate the ignition coil and fuel injec-
tor.
