low beam MITSUBISHI 380 2005 Owner's Manual

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-291
DIAGNOSIS
Required Special Tool:
MB991223: Harness Set
STEP 1. Check the headlamp operation.
Q: Which of the headlamps does not illuminate?
LH (low beam) : Go to Step 2.
RH (low beam) : Go to Step 6.
LH (only low-beam) : Go to Step 10.
RH (only low-beam) : Go to Step 13.
LH (only high beam) : Go to Step 16.
RH (only high beam) : Go to Step 21.
Low beam only (both RH and LH) : Refer to Inspection
Procedure H-2 "The headlamps (low-beam) do not
illuminate normally P.54B-264."
High beam only (both RH and LH) : Refer to Inspection
Procedure H-3 "The headlamps (high-beam) do not
illuminate normally P.54B-268."
High beam indicator lamp : Refer to Inspection Procedure
H-8 "The high-beam indicator lamp does not
illuminate P.54B-301."
STEP 2. Check headlamp (LH) connector A-20 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is headlamp (LH) connector A-20 in good condition?
YES : Go to Step 3.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Check that the headlamps illuminate
normally.
STEP 3. Check headlamp (LH) bulb.
(1) Remove the headlamp (LH) bulb.
(2) Verify that the headlamp (LH) bulb is not damaged or
burned out.
Q: Is headlamp (LH) bulb normal?
YES : Go to Step 4.
NO : Replace the headlamp (LH) bulb. Verify that the
headlamps illuminate normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-304
STEP 4. Use Diagnostic Tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the ETACS-ECU.
Connect special tool MB991910 before connecting special
tool MB991812. Be sure to connect special tool MB991806
after turning on special tool MB991824.
(1) Connect the SWS monitor. Refer to "How to connect SWS
monitor P.54B-13."
(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Operate Diagnostic Tool MB991958 according to the
procedure below to display "ECU COMM Check."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "ECU COMM Check."
(4) Diagnostic Tool MB991958 should show "OK" on the "ECU
COMM Check" menu for the "ETACS ECU" menu.
Q: Is "OK" displayed for the "ETACS ECU" menu?
YES : Go to Step 5.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."
STEP 5. Replace the combination meter.
(1) Replace the combination meter.
(2) Check that the high beam indicator lamp illuminates
normally.
Q: Does the high beam indicator lamp illuminate normally?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. Check that the high beam
indicator lamp illuminates normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-339
FOG LAMP
GENERAL DESCRIPTION CONCERNING THE FOG LAMPSM1549021400216
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80The following ECUs affect the functions and control
of the fog lamps.
Fog lamp
The fog lamps will illuminate only when the fog lamp
switch is operated while the low-beam headlamps
are on.
The fog lamps will be switched off when any of the
following conditions is met. The fog lamps will also
be switched off automatically by headlamp automatic
shutoff function.
When the high-beam headlamps are switched
on, the fog lamps will be switched off. If the
low-beam headlamps are switched on again, the
fog lamps will illuminate again.
When the headlamp switch is turned off or the tail
lamps and headlamps are off, the fog lamps will
be switched off. If the low-beam headlamps are
switched on again, the fog lamps will not illumi-
nate again.
Fog lamp indicator
At the same time that the fog lamps are illuminated, the
ETACS-ECU sends a signal to illuminate the fog lamp indicator
via the CAN bus line. The combination meter receives the
transmitted signal and turns the fog lamp indicator on and off. FUNCTION CONTROL ECU
Fog lamp ETACS-ECU, front-ECU, column switch
Fog lamp indicator ETACS-ECU, column switch

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-340
INSPECTION PROCEDURE J-1: Fog Light: Fog lamps do not illuminate when the fog lamp switch is
turned on.
NOTE: This troubleshooting procedure requires the
use of Diagnostic Tool MB991958 and SWS monitor
kit MB991813. For details on how to use the SWS
monitor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The ETACS-ECU sends a fog lamp illumination
request signal ("LAMP ON" signal) to the
front-ECU when the fog lamp switch is turned on
while the headlamps are illuminating at low
beam.
Then the front-ECU switches on its relay to illumi-
nate the fog lamps.
.
TECHNICAL DESCRIPTION (COMMENT)
If the headlamps illuminate at low beam, the fog
lamp relay, the fog lamp switch, the front-ECU or the
ETACS-ECU may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
Trouble in input signal system
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
The fog lamp relay may be defective
The front-ECU may be defective
The ETACS-ECU may be defective
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
MB991813: SWS Monitor Kit
MB991806: SWS Monitor Cartridge
MB991812: SWS Monitor Harness (For Column-ECU)
MB991822: Test Probe Harness
STEP 1. Check the headlamp (low-beam) operation.
Q: Do the headlamps illuminate at low beam normally?
YES : Go to Step 2.
NO : Refer to Inspection Procedure H-2 "The headlamps
(low-beam) do not illuminate normally P.54B-264."

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-345
INSPECTION PROCEDURE J-2: Fog Light: Fog lamps do not go out when the headlamps (low-beam)
are turned off while the fog lamps are on.
.
TECHNICAL DESCRIPTION (COMMENT)
If the trouble above occurs, the front-ECU may be
defective.
.
TROUBLESHOOTING HINT
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The front-ECU may be defective
DIAGNOSIS
Replace the front-ECU.
The fog lamps should go out when the headlamps (low-beam)
are turned off while the fog lamps are on.
INSPECTION PROCEDURE J-3: Fog Light: One of the fog lamps does not illuminate.
.
TECHNICAL DESCRIPTION (COMMENT)
If one of the fog lamps does not illuminate, the fog
lamp relay or the fog lamp bulb may be defective. If
the fog lamp indicator lamp does not illuminate, the
combination meter may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
The fog lamp bulb may be defective
.
DIAGNOSIS
Required Special Tool:
MB991223: Harness Set

INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-420
INSPECTION PROCEDURE M-5: Column Switch: ETACS-ECU does not receive any signal from the
taillamp switch, the headlamp switch, the passing lamp switch, the dimmer switch or the turn-signal
lamp switch.
NOTE: This troubleshooting procedure requires the
use of diagnostic tool MB991958 and SWS monitor
kit MB991813. For details on how to use the SWS
monitor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The ETACS-ECU operates the following equipment
or functions according to signal from the column
switch (turn-signal lamp and lighting switch):
Light reminder tone alarm function
Turn-signal lamp buzzer
Headlamp
Turn-signal lamp
High-beam indicator
Turn-signal indicators
.
TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the equipment or functions
described in "CIRCUIT OPERATION" do not work
normally. If the signal is not normal, the column
switch (turn-signal lamp and lighting switch) or the
ETACS-ECU may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The column switch (turn-signal lamp and lighting
switch) may be defective
The ETACS-ECU may be defective
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
MB991813: SWS Monitor Kit
MB991806: SWS Monitor Cartridge
MB991812: SWS Monitor Harness (For Column-ECU)
MB991822: Test Probe Harness

CHECK AT ECU TERMINAL
SIMPLIFIED WIRING SYSTEM (SWS)54B-484
FRONT-ECU
NOTE: Terminal voltages cannot be measured as the
front-ECU is installed directly on the relay box.
Therefore, this information is only for reference.
TERMINAL
NO.INSPECTION ITEM INSPECTION CONDITION NORMAL VALUE
1 Output to fog lamp relay When the fog lamps are on Battery positive voltage
2 Output to headlamp (high-beam) When headlights (high-beam)
are onBattery positive voltage
3, 4 Battery power supply (for
headlamp)Always Battery positive voltage
5 Battery power supply (for
taillamp)Always Battery positive voltage
6 Output to headlamp (low-beam) When headlights (low-beam) are
onBattery positive voltage
7 Battery power supply (for ECU) Always Battery positive voltage
8 Output to taillamps When taillamps are on Battery positive voltage
9
11
21 Output to windshield washer When windshield washer is on Battery positive voltage
22 SWS communication line Always 0
12 V (pulse signal)
23 Input of automatic stop signal to
windshield wiperWhen windshield wiper is on Battery positive voltage
24 Power supply to ignition switch
(ACC)Ignition switch: "ACC" Battery positive voltage
25 Input of backup signal from
headlamp switchHeadlamp switch: ON0 V
26 Input of backup signal to
windshield wiperWindshield low-speed wiper
switch or windshield high-speed
wiper switch: ON0 V
27 Output to windshield wiper
(low-speed)When windshield wiper is on (at
low speed)Battery positive voltage
28 Output to windshield wiper
(high-speed)When windshield wiper is on (at
high speed)Battery positive voltage
30 Power supply to ignition switch
(IG2)Ignition switch: "ON" Battery positive voltage
31 Ground Always 0 V

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.