2005 MITSUBISHI 380 Speed

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-5
INSPECTION PROCEDURE 3: Radiator Fan and Condenser Fan do not Operate
.
CIRCUIT OPERATION
The fan controller is powered from fusible link
No.2.
The engine-ECU uses input signals from the A/C
switch, the water temperature sensor unit and the
vehicle speed sensor or the output shaft
speed sensor to control the speed of the
radiator fan motor and the condenser fan motor.
The engine-ECU controls the fan controller to
activate the radiator fan motor and the condenser
fan motor.
.
TECHNICAL DESCRIPTION
The cause could be a malfunction of the fan con-
troller power supply or earth circuit.
If the communication line wiring harness between
the fan controller and the engine-ECU is
short-circuited to earth, the radiator fan motor
and the condenser fan motor will not rotate.
The cause could also be a malfunction of input
signal from the A/C switch, the water temperature
sensor unit and the vehicle speed sensor
or the output shaft speed sensor to the
engine-ECU.
The cause could also be a malfunction of the fan
controller or the engine-ECU.

.
TROUBLESHOOTING HINTS
Malfunction of fusible link No.2
Malfunction of fan control relay
Malfunction of cooling fan motor and fan control-
ler
Malfunction of engine-ECU.
Damaged wiring harness or connector
Refer to component locations GROUP-1
Refer to configuration diagrams GROUP-1
Refer to circuit diagrams GROUP-1

ENGINE COOLING DIAGNOSIS
ENGINE COOLING14-20
STEP 23. MUT-III self-diag code
Check if an MPI system self-diag code is set. (Refer to GROUP
13A - Trouble shooting 13A-5).
Q: Diagnosis code set?
YES : Inspection chart for diagnosis code (Refer to GROUP
13A - Trouble shooting 13A-17)
NO : Replace the engine-ECU (Refer to GROUP 13A,
Engine-ECU 13A-675 ). Then go to Step 24.
STEP 24. Check the symptoms.
Q: Does the radiator fan motor and the condenser fan
motor operate correctly?
YES : This symptom is complete.
NO : Return to Step 1.
INSPECTION PROCEDURE 4: Radiator Fan and Condenser Fan do not Change Speed or Stop
.
Radiator Fan and Condenser Fan Drive
Circuit
Refer to 5.
.
TECHNICAL DESCRIPTION
The cause could be a malfunction of the fan con-
troller power supply or earth circuit.
If the communication line wiring harness between
the fan controller and the engine-ECU is
short-circuited to earth, the radiator fan motor
and the condenser fan motor will not rotate.
The cause could also be a malfunction of input
signal from the A/C switch, the water temperature
sensor unit and the vehicle speed sensor
or the output shaft speed sensor to the
engine-ECU.
The cause could also be a malfunction of the fan
controller or the engine-ECU.
.
TROUBLESHOOTING HINTS
Malfunction of fusible link No.2
Malfunction of fan control relay
Malfunction of cooling fan motor
Malfunction of fan controller
Malfunction of engine-ECU
Damaged wiring harness or connector
DIAGNOSIS
STEP 1. Check the fan control relay.
Refer to 14-31.
Q: Is the fan control relay in good condition?
YES : Go to Step 2.
NO : Replace the fan control relay. Then go to Step 8.

THERMOSTAT
ENGINE COOLING14-36
14. ENGINE COOLANT
TEMPERATURE SENSOR
CONNECTOR
15. CAPACITOR CONNECTOR
16. CAMSHAFT POSITION SENSOR
CONNECTOR
17. INHIBITOR SWITCH SENSOR
CONNECTOR
18. A/T CONTROL SOLENOID VALVE
ASSEMBLY CONNECTOR
19. OUTPUT SHAFT SPEED
SENSOR CONNECTOR
20. INPUT SHAFT SPEED SENSOR
CONNECTOR REMOVAL STEPS (Continued)
REMOVAL STEPS
<> >>B<<21. RADIATOR LOWER HOSE
CONNECTION22. WATER INLET FITTING>>A<<23. THERMOSTATREMOVAL STEPS (Continued)

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.

CHARGING SYSTEM
ENGINE ELECTRICAL16-6
SPECIAL TOOLM1161000600486
TOOL TOOL NUMBER AND
NAMESUPERSESSION APPLICATION
Diagnostic tool (MUT-III)
A: MB991824
Ve h i c l e
communication
interface (V.C.I.)
B: MB991827
MUT-III USB cable
C: MB991910
MUT-III main harness
A (Vehicles with CAN
communication
system)
D: MB991911
MUT-III main harness
B (Vehicles without
CAN communication
system)
E: MB991914
MUT-III main harness
C (for Daimler Chrysler
models only)
F: MB991825
MUT-III measurement
adapter
G: MB991826
MUT-III trigger
harnessMB991824-KIT
NOTE: G: MB991826
MUT-III Trigger Harness
is not necessary when
pushing V.C.I. ENTER
key.Checking of engine
speed
For vehicles with CAN
communication, use
MUT-III main harness A
to send simulated
vehicle speed. If you
connect MUT-III main
harness B instead, the
CAN communication
does not function
correctly.
MB998467
Alternator harness
connectorMIT530
Micrd 530 charging
system tester.Checking of alternator
("S" terminal voltage)

CHARGING SYSTEM
ENGINE ELECTRICAL16-8
10.With the engine running at 2,500 r/min, turn the
headlights and other lights on and off to adjust the
alternator load so that the value displayed on the
ammeter is slightly above 30 A.
Read the voltmeter. Voltage reading at or below
limit value means voltage drop between alternator
and battery is OK.
Limit value: maximum 0.3 V
NOTE: When the alternator output is high and the
value displayed on the ammeter does not
decrease to 30 A, set the value to 40 A. Read the
value displayed on the voltmeter at this time.
In this case the limit value becomes maximum 0.4
V.
Adjust the engine speed by gradually decreasing
it until the value displayed on the ammeter is 30
A. Take a reading of the value displayed on the
voltmeter at this time.11.If the value displayed on the voltmeter is above
the limit value, there is probably a malfunction in
the alternator output wire. Check the wiring
between the alternator "B" terminal and the
positive battery terminal (including fusible link).
If a terminal is not sufficiently tight or if the
harness has become discolored due to
overheating, repair and then test again.
12.After the test, run the engine at idle.
13.Turn off all lights and turn the ignition switch to the
"LOCK" (OFF) position.
14.Disconnect the engine tachometer or diagnostic
tool.
15.Disconnect the negative battery cable.
16.Disconnect the ammeter and voltmeter.
17.Connect the negative battery cable.
18.Run the engine for 10 minutes at an idle.
OUTPUT CURRENT TESTM1161001000670

CHARGING SYSTEM
ENGINE ELECTRICAL16-9
Required Special Tool:
: Diagnostic Tool (MUT-III)
MB991824: V.C.I.
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
This test determines whether the alternator outputs
normal current. For best results, use a charging sys-
tem tester. If not available, follow the steps below.
Battery posts, terminals and related acces-
sories contain lead and lead compounds.
WASH HANDS AFTER HANDLING.
1. Before the test, always be sure to check the
following.
Alternator installation
Battery (Refer to GROUP 54A, Chassis Electrical
Battery On-vehicle Service Battery Check
P.54A-5.)
NOTE: The battery to be used should be slightly
discharged. The load in a fully-charged battery
will be insufficient and the test may not be able to
be carried out correctly.
Alternator drive belt tension (Refer to GROUP 00,
General
Maintenance Service Drive Belts
(For Alternator, Power Steering Pump and Air
Conditioning) (Check) P.00-39.)
Fusible link
Abnormal noise from the alternator while the
engine is running.
2. Turn the ignition switch to the "LOCK" (OFF)
position.
3. Disconnect the negative battery cable.
Never use clips to connect the wire. Loose
connections (for example, using clips) will
lead to a serious accident because of high
current.
4. Connect a clamp-type DC test ammeter with a
range of 0
120 A to the alternator "B" terminal
output wire.
5. Connect a voltmeter with a range of 0
20 V
between the alternator "B" terminal and ground.
(Connect the positive lead of the voltmeter to the
"B" terminal, and then connect the negative lead
of the voltmeter to ground.)
6. Connect the negative battery cable.
7. Connect an engine tachometer or diagnostic tool.
8. Leave the hood open.9. Check to be sure that the reading on the voltmeter
is equal to the battery positive voltage.
NOTE: If the voltage is 0 V, the cause is probably
an open circuit in the wire or fusible link between
the alternator "B" terminal and the battery positive
terminal or malfunctioning voltmeter.
10.After turning on the headlights, start the engine.
NOTE: Because the current from the battery will
soon drop after the engine is started, step 11
should be carried out as quickly as possible in
order to obtain the maximum current output value.
11.Immediately after setting the headlights to high
beam and turning the heater blower switch to the
highest position, increase the engine speed to
2,500 r/min and read the maximum current output
value displayed on the ammeter.
Limit value: 70 % of nominal current output
NOTE: For the nominal current output, refer to the
Alternator Specifications.
NOTE: The current output value will depend on
the electrical load and the temperature of the
alternator body.
NOTE: If the electrical load is small while testing,
the specified level of current may not be output
even though the alternator is normal. In such
cases, increase the electrical load by leaving the
headlights turned on for some time to discharge
the battery or by using the lighting system in
another vehicle, and then test again.
NOTE: The specified level of current also may not
be output if the temperature of the alternator body
or the ambient temperature is too high. In such
cases, cool the alternator and then test again.
12.The reading on the ammeter should be above the
limit value. If the reading is below the limit value
and the alternator output wire is normal, remove
the alternator from the engine and check the
alternator.
13.Run the engine at idle speed after the test.
14.Turn the ignition switch to the "LOCK" (OFF)
position.
15.Disconnect the engine tachometer or diagnostic
tool.
16.Disconnect the negative battery cable.
17.Disconnect the ammeter and voltmeter .
18.Connect the negative battery cable.
19.Run the engine for 10 minutes at an idle.

CHARGING SYSTEM
ENGINE ELECTRICAL16-11
11.Increase the engine speed to 2,500 r/min.
12.Read the value displayed on the voltmeter when
the current output by the alternator becomes 10 A
or less.
13.If the voltage reading conforms to the value in the
voltage regulation table, then the voltage regulator
is operating normally.
If the voltage is outside the standard value, there
is a malfunction of the voltage regulator or the
alternator (Refer to the following table).14.After the test, lower the engine speed to idle.
15.Turn the ignition switch to the "LOCK" (OFF)
position.
16.Disconnect the engine tachometer or diagnostic
tool .
17.Disconnect the negative battery cable.
18.Disconnect the ammeter and voltmeter.
19.Connect the negative battery cable.
20.Run the engine for 10 minutes at an idle.
VOLTAGE REGULATION TABLE
WAVE PATTERN CHECK USING AN
OSCILLOSCOPE
M1161001200180.
MEASUREMENT METHOD
Connect the oscilloscope special patterns pick-up to the
alternator "B" terminal.
.
STANDARD WAVEFORM
INSPECTION TERMINAL VOLTAGE REGULATOR
AMBIENT TEMPERATURE [
C
(
F)]STANDARD VALUE (V)
Te r m i n a l " S "
20 (4)14.2 15.4
20 (68) 13.9
14.9
60 (140) 13.4
14.5
80 (176) 13.1
14.2
Observation Conditions
FUNCTION SPECIAL PATTERNS
Pattern height Variable
Variable knob Adjust while viewing the wave
pattern
Pattern selector Raster
Engine revolutions Curb idle speed