2005 MITSUBISHI 380 electrical

HOW TO DIAGNOSE
GENERAL 00E-7
CHECKING SWITCHESM1001004800144
In a circuit diagram, a switch is shown in the idle state.
1. Normally open or normally closed switch
Switches are classified into those which open the circuit and
those which close the circuit when off.
Switches are shown in their normal state unless specified
otherwise.
2. Switch connection
This figure illustrates a complex switch. The continuity
between terminals at each position is as indicated in the
table below.
SWITCH
POSITIONTESTER
CONNECTIONSPECIFIED
CONNECTION
OFF
1st stage 156 Continuity
2nd stage 1
46 Continuity
3rd stage 1
36 Continuity
4th stage 1
26 Continuity

HOW TO DIAGNOSE
GENERAL 00E-8
CHECKING RELAYSM1001004900152
1. By using a relay, a heavy current can be turned on and off by
a switch using much less current. For example, in the circuit
shown here, when the switch is turned on (closed), current
flows to the coil of the relay. Then, its contact is turned on
(closed) and the light comes on. The current flowing through
the switch is much less than that for the light.
2. When current flows through the coil of a relay, its core is
magnetized to attract the iron piece, closing (ON) the
contact at the tip of the iron piece. When the coil current is
turned off, the iron piece returns to its original position by a
spring, opening the contact (OFF).
3. Relays may be classified as the normally open-type or the
normally closed-type, depending on their contact
construction.
NOTE: The deenergised state means that no current is flow-
ing through the coil. The energised state means that current
is flowing through the coil.
(1) The normally open-type
When a normally open relay as illustrated here is
checked, there should be no continuity between terminals
3 and 4 when the relay is deenergised. There should be
continuity between terminals 3 and 4 when battery
voltage and ground are applied to terminals 1 and 2. The
relay condition is determined by this check.
NOTE: Check the relay in both situation which is
energised and is not energised.
(2) The normally closed-type
When a normally closed relay as illustrated here is
checked, there should be continuity between terminals 3
and 4 when the relay is deenergised. There should be no
continuity between terminals 3 and 4 when battery
voltage and ground are applied to terminals 1 and 2. The
relay condition is determined by this check.
NOTE: Check the relay in both situation which is
energised and is not energised.

HOW TO DIAGNOSE
GENERAL 00E-9
CABLES AND WIRES CHECKM1001005100041
1. Check connections for looseness, rust, and stains.
2. Check terminals and wires for corrosion.
3. Check terminals and wires for open circuit or impending
open circuit.
4. Check wire insulation and coating for damage, cracks, and
wear.
5. Check conductive parts of terminals for contact with other
metallic parts (vehicle body and other parts).
6. Check grounding parts to verify that there is complete
continuity between attaching bolt(s) and vehicle body.
7. Check for incorrect wiring.
8. Check that harnesses are secured to prevent contact with
sharp edges and corners or hot parts (exhaust manifold,
pipe, etc.).
9. Check that harnesses are secured firmly to provide enough
clearance from the fan pulley, fan belt, and other rotating or
moving parts.
10.Check that the harnesses between fixed parts (such as the
vehicle body) and vibrating parts (such as the engine) are
long enough to allow for vibration and movement.
BATTERY HANDLINGM1001005200048
Battery posts, terminals and related accessories con-
tain lead and lead compounds. WASH HANDS AFTER
HANDLING.
When checking or servicing does not require power from the
vehicle battery, be sure to disconnect the cable from the battery
(
) terminal. This will prevent problems that could be caused by
a short circuit. Disconnect the (
) battery terminal first and
reconnect it last.
GENERAL ELECTRICAL SYSTEM CHECKM1001005300045
A circuit consists of the power supply, switch, relay, load,
ground, etc. There are various methods to check a circuit
including an overall check, voltage check, short-circuit check,
and continuity check. Each of the methods briefly described
below applies only to circuits similar to the illustration.

HOW TO DIAGNOSE
GENERAL 00E-10
1. VOLTAGE CHECK
(1) Ground one lead wire of the test light. If a voltmeter is
used instead of the test light, ground the grounding side
lead wire.
(2) Connect the other lead wire of the test light to the power
side terminal of the switch connector. The test light
should come on or the voltmeter should indicate a
voltage.
(3) Then, connect the test light or voltmeter to the motor
connector. The test light should not come on, or the
voltmeter should indicate no voltage. When the switch is
turned ON in this state, the test light should come on, or
the voltmeter should indicate a voltage, with the motor
starting to run.
(4) The circuit illustrated here is normal. If there is any
problem, such as the motor failing to run, check voltages
beginning at the connector nearest to the motor until the
faulty part is identified.
2. SHORT-CIRCUIT CHECK
Because the fuse has blown, it is probable that there is a
short circuit. Follow the procedures below to narrow down
the short-circuit location.
STEP 1. Remove the blown fuse and connect the test light
across the fuse terminals (Circuit switch: OFF).
Q: Does the test light illuminate?
YES : Short-circuit exists between the fuse block and the
switch. Diagnose the harness between the fuse block
and the switch.
NO : Go to Step 2.

HOW TO DIAGNOSE
GENERAL 00E-11
STEP 2. Turn the switch ON and disconnect the
illumination light connector.
Q: Does the test light illuminate?
YES : Short-circuit exists between the switch and the
connector. Diagnose the harness between the switch
and the connector.
NO : Short-circuit exists between the connector and the
illumination light. Diagnose the harness between the
connector and the illumination light.

HOW TO DIAGNOSE
GENERAL 00E-12
3. CONTINUITY CHECK
(1) When the switch is in the "OFF" position and the contact
points of terminals 1 and 2 are connected, the
self-powered test light should illuminate or the ohmmeter
should read 0 ohm.
(2) When the switch is the "ON" position and the contact
points of terminals 3 and 4 are connected, the
self-powered test light should come on or the ohmmeter
should read 0 ohm.

16-1
GROUP 16
ENGINE
ELECTRICAL
CONTENTS
CHARGING SYSTEM . . . . . . . .
16-2
GENERAL DESCRIPTION . . . . . .
16-2
CHARGING SYSTEM DIAGNOSIS16-3
SPECIAL TOOL . . . . . . . . . . . . . . .16-6
ON-VEHICLE SERVICE. . . . . . . . .16-7
ALTERNATOR OUTPUT WIRE VOLTAGE
DROP TEST . . . . . . . . . . . . . . . . . . . . . 16-7
OUTPUT CURRENT TEST . . . . . . . . . . 16-8
REGULATED VOLTAGE TEST . . . . . . . 16-10
WAVE PATTERN CHECK USING AN
OSCILLOSCOPE . . . . . . . . . . . . . . . . . . 16-11
ALTERNATOR ASSEMBLY . . . . .16-14
REMOVAL AND INSTALLATION . . . . . 16-14
DISASSEMBLY AND ASSEMBLY. . . . . 16-15
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-17
STARTING SYSTEM . . . . . . . . .16-20
GENERAL DESCRIPTION . . . . . .
16-20
STARTING SYSTEM DIAGNOSIS . . . . 16-21
STARTER MOTOR ASSEMBLY . .16-23
REMOVAL AND INSTALLATION . . . . . 16-23
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-24
DISASSEMBLY AND ASSEMBLY. . . . . 16-26
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-28
IGNITION SYSTEM . . . . . . . . . . . . . .16-30GENERAL DESCRIPTION . . . . . . .
16-30
SPECIAL TOOLS . . . . . . . . . . . . . .16-30
ON-VEHICLE SERVICE . . . . . . . . .16-31
KNOCK CONTROL SYSTEM CHECK . . 16-31
IGNITION COIL CHECK. . . . . . . . . . . . . 16-31
SPARK PLUG TEST . . . . . . . . . . . . . . . 16-32
SPARK PLUG CHECK AND CLEANING16-32
CAMSHAFT POSITION SENSOR CHECK16-32
CRANKSHAFT POSITION SENSOR
CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . 16-32
IGNITION COIL . . . . . . . . . . . . . . . .16-33
REMOVAL AND INSTALLATION . . . . . 16-33
CAMSHAFT POSITION SENSOR .16-34
REMOVAL AND INSTALLATION . . . . . 16-34
CRANKSHAFT POSITION SENSOR16-35
REMOVAL AND INSTALLATION . . . . . 16-35
KNOCK SENSOR . . . . . . . . . . . . . .16-36
REMOVAL AND INSTALLATION . . . . . 16-36
SPECIFICATIONS . . . . . . . . . . 16-38
FASTENER TIGHTENING
SPECIFICATIONS . . . . . . . . . . . . .
16-38
GENERAL SPECIFICATIONS . . . .16-38
SERVICE SPECIFICATIONS . . . . .16-39

16-2
CHARGING SYSTEM
GENERAL DESCRIPTIONM1161000100629
The charging system charges the battery with the
alternator output to keep the battery charged at a
constant level during varying electrical load.
OPERATION
Rotation of the excited field coil generates AC volt-
age in the stator.
This alternating current is rectified through diodes to
DC voltage having a waveform shown in the illustra-
tion above.
The average output voltage fluctuates slightly with
the alternator load condition.When the ignition switch is turned on, current flows in
the field coil and initial excitation of the field coil
occurs.
When the stator coil begins to generate power after
the engine is started, the field coil is excited by the
output current of the stator coil.
The alternator output voltage rises as the field cur-
rent increases and it falls as the field current
decreases. When the battery positive voltage
(alternator S terminal voltage) reaches a regulated
voltage of approximately 14.4 V, the field current is
cut off. When the battery positive voltage drops
below the regulated voltage, the voltage regulator
regulates the output voltage to a constant level by
controlling the field current.
In addition, when the field current is constant, the
alternator output voltage rises as the engine speed
increases.