2005 MITSUBISHI 380 Workshop Manual

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-337
STEP 3. Using Diagnostic Tool MB991958, read the
combination meter diagnostic trouble code.
Check whether the combination meter-related DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check whether a combination meter-related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the combination meter. Refer to P.54A-48.
NO : Go to Step 4.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-338
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 "ON" 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 turn-signal lamp indicator lamps illuminate
normally.
Q: Are the turn-signal indicator lamps in good condition?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. Check that the turn-signal
lamp indicator lamps illuminate 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-341
STEP 2. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Set each switch to the following condition before checking input
signal from the fog lamp switch:
Ignition switch: ON
Fog lamp switch: ON
NOTE: Turn the ignition switch to the "ON" position in order to
disable the headlamp automatic shutdown function.
To prevent damage to Diagnostic Tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting Diagnostic Tool
MB991958. Connect special tool MB991910 before con-
necting special tool MB991812. Be sure to connect special
tool MB991806 after turning on special tool MB991824.
(1) Connect the special tool. Refer to "How to connect SWS
monitor P.54B-13."
(2) Operate Diagnostic Tool MB991958 according to the
procedure below to display "F.FOG."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "LIGHTING."
g. Select "F.FOG."
(3) Check that normal conditions are displayed for the items
described in the table below.
Q: Does the Diagnostic Tool MB991958 display the items
"IG SW (IG1)" and "F.FOG LAMP" as normal condition?
Normal conditions are displayed for all the items : Go to
St e p 3 .
Normal condition is not displayed for "IG SW (IG1)" :
Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408."
Normal condition is not displayed for "F.FOG LAMP" :
Refer to Inspection Procedure M-3 "ETACS-ECU
does not receive any signal from the fog lamp switch
P.54B-410." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 30 IG SW (IG1) ON
ITEM 36 F.FOG LAMP ON

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-342
STEP 3. Check fog lamp relay connector A-05X for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is fog lamp relay connector A-05X in good condition?
YES : Go to Step 4.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Verify that the fog lamps illuminate normally.
STEP 4. Check the fog lamp relay.
Q: Is the fog lamp relay in good condition?
YES : Go to Step 5.
NO : Replace the fog lamp relay. Verify that the fog lamps
illuminate normally.
BATTERY VOLTAGE TESTER
CONNECTIONSPECIFIED
CONDITION
Not applied 1
4 Open circuit
Connect terminal 2
to the positive
battery terminal
Connect terminal 3
to the negative
battery terminal1
4 Less than 2 ohms

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-343
STEP 5. Check the battery power supply circuit to the fog
lamp relay. Measure the voltage at fog lamp relay
connector A-05X.
The top and bottom of the fog lamp relay are difficult to
identify. Prior to inspection, confirm the triangle mark on
the relay box.
(1) Disconnect fog lamp relay connector A-05X and measure
the voltage available at the relay box side of the connector.
(2) Measure the voltage between terminal 1 and ground, and
also between terminal 2 and ground.
The voltage should measure approximately 12 volts
(battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery
positive voltage)?
YES : Go to Step 7.
NO : Go to Step 6.
STEP 6. Check the wiring harness between fog lamp relay
connector A-05X (terminals 1 and 2) and the battery.
Q: Is the wiring harness between fog lamp relay connector
A-05X (terminals 1 and 2) and the battery in good
condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. Verify that
the fog lamps illuminate normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-344
STEP 7. Check front-ECU connector A-11X for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is front-ECU connector A-11X in good condition?
YES : Go to Step 8.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Verify that the fog lamps illuminate normally.
STEP 8. Check the wiring harness between fog lamp relay
connector A-05X (terminal 3) and front-ECU connector
A-11X (terminal 11).
Q: Is the wiring harness between fog lamp relay connector
A-05X (terminal 3) and front-ECU connector A-11X
(terminal 11) in good condition?
YES : Go to Step 9.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. Verify that
the fog lamps illuminate normally.
STEP 9. Replace the ECU.
(1) Replace the front-ECU.
(2) The fog lamps should illuminate normally.
Q: Do the fog lamps illuminate normally?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. Verify that the fog lamps
illuminate normally.