2005 MITSUBISHI 380 Tail light

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-98
54B
INSPECTION PROCEDURE B-2: Tone Alarm: Light Reminder Tone Alarm Function does not Work
Normally.
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 light reminder tone
alarm function according to the following signals:
Ignition switch (IG1): OFF
Ignition key reminder switch: ON
Front door switch (RH): ON
Taillamp switch: ON
Headlamp switch: ON
The ETACS-ECU operates the lamp reminder tone
alarm function under the following conditions:
Ignition switch: "LOCK" (OFF) position
Ignition key: Removed from the ignition key cylin-
der
Driver’s door: open
Taillamps or headlamps: ON
.
TECHNICAL DESCRIPTION (COMMENT)
If the function does not work normally, the input cir-
cuit system from the switches or the ETACS-ECU
may be defective (refer to "CIRCUIT OPERATION").
.
TROUBLESHOOTING HINTS
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 ETACS-ECU may be defective
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
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

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-100
STEP 2. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: OFF (key removed)
Lighting switch: TAIL or HEAD
Driver’s door: open
Front passenger's door: closed
(1) Operate diagnostic tool MB991958 according to the
procedure below to display "LGT MONI. ALRM."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "BUZZER."
g. Select "LGT MONI. ALRM."
(2) Check that normal conditions are displayed for the items
described in the table below.
NOTE: diagnostic tool MB991958 display changes when
the driver's or the front passenger's door is opened. If any of
the doors is open, the system cannot be checked correctly.
Q: Does diagnostic tool MB991958 display "HEADLAMP
SW", "TAILLAMP SW", "IG SW IG1", "FRONT DOOR
SW", "H/L AUTO-CUT" and "BUZZER" as normal
condition?
Normal conditions are displayed for all the items :
Replace the ETACS-ECU. The lamp reminder tone
alarm function should now work normally.
Normal condition is not displayed for "HEADLIGHT SW"
: Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the headlamp switch
P.54B-420."
Normal condition is not displayed for "TAILLIGHT SW" :
Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the taillamp switch
P.54B-420."
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." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 00 HEADLAMP SW Either of items is ON
ITEM 01 TAILLAMP SW
ITEM 30 IG SW IG1 OFF
ITEM 32 FRONT DOOR SW ON
ITEM 35 H/L AUTO-CUT OFF
ITEM 43 BUZZER ON

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-259
Headlamp automatic-shutdown function
Even if the lighting switch (taillamps switch or headlamp switch)
is ON, the headlamps (including the taillamps) will automati-
cally go off in the following conditions to prevent the battery
from discharging as a result of forgetting to turn off lamps.
If the ignition key is turned from "ON" to "LOCK" (OFF) or
"ACC" position with the lighting switch turned ON, and this
state continues for three minutes, the headlamps will automati-
cally be turned off. If the driver's seat door is opened during
these three minutes, the headlamps will go off one second
later.
NOTE: The headlamp automatic-shutoff function can be cus-
tomized on vehicles equipped with a multi center display (mid-
dle grade type). Refer to P.54B-486.
Dimmer automatic reset function
If the headlamp switch is turned off while the high-beam
headlamps are on, the dimmer switch will be reset. Because of
this, the headlamps will illuminate at low beam the next time
that they are turned on. The dimmer switch will be also reset if
the dimmer switch is turned on unintentionally while the pass-
ing switch is operated.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-260
INSPECTION PROCEDURE H-1: Headlamp and Taillamp: The taillamps do not illuminate normally.
NOTE: This troubleshooting procedure requires the
use of Diagnostic Tool MB991958 and SWS monitor
kit MB991813. For details on how to connect the
SWS monitor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
When the lighting switch is set to "TAIL" position, the
"TAIL" signal is sent through the column-ECU (incor-
porated in the column switch) to the front-ECU. If the
front-ECU receives the "TAIL" signal through the col-
umn-ECU, the front-ECU turns on the taillamp relay
(incorporated in the front-ECU), thus causing the
taillamps to illuminate.
.
TECHNICAL DESCRIPTION (COMMENT)
If the taillamps do not illuminate normally, the column
switch or the front-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 front-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

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-262
STEP 2. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: ON
Lighting switch: TAIL
NOTE: Turn the ignition switch to the "ON" position in order to
disable the headlamp automatic shutdown function.
(1) Operate Diagnostic Tool MB991958 according to the
procedure below to display "TAILLAMP."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "LIGHTING."
g. Select "TAILLAMP."
(2) Check that normal conditions are displayed for the items
described in the table below.
Q: Does the Diagnostic Tool MB991958 display the items
"TAILLAMP SW", "H/L AUTO-CUT" and "FRONT ECU
ACK" as normal condition?
Normal conditions are displayed for all the items : Go to
St e p 3 .
Normal condition is not displayed for "TAILLAMP SW" :
Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the taillamp switch
P.54B-420."
Normal condition is not displayed for "H/L AUTO-CUT" :
Refer to Inspection Procedure H-9 "Headlamp
automatic shutoff function does not work normally
P.54B-305."
Normal condition is not displayed for "FRONT ECU
ACK" : Replace the front-ECU. Verify that the taillamps
illuminate normally. ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 01 TAILLAMP SW ON
ITEM 35 H/L AUTO-CUT OFF
ITEM 70 FRONT ECU ACK NORMAL ACK

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-264
STEP 5. Check the wiring harness between front-ECU
connector A-11X (terminal 7) and the battery.
Q: Is the wiring harness between front-ECU connector
A-11X (terminal 7) 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 taillamps illuminate normally.
INSPECTION PROCEDURE H-2: Headlamp and Taillamp: The headlamps (low-beam) do not illuminate
normally.
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
When the lighting switch is set to "HEAD" posi-
tion, the "HEAD" signal is sent through the col-
umn-ECU (incorporated in the column switch) to
the front-ECU. If the front-ECU receives the
"HEAD" signal through the column-ECU, the
front-ECU turns on the headlamp relay (incorpo-
rated in the front-ECU), thus causing the
headlamps to illuminate. The headlamps always
illuminate at low-beam by the headlamp dimmer
switch automatic resetting function.
If the SWS communication line is defective, the
front-ECU operates the headlamps by using the
other communication lines (headlamp backup cir-
cuit) instead of that line.
.
TECHNICAL DESCRIPTION (COMMENT)
If the headlamps (low-beam) do not illuminate nor-
mally, the column switch or the front-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 front-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

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-273
INSPECTION PROCEDURE H-5: Headlamp and Taillamp: Headlamps do not illuminate when the
lighting switch is at "TAIL," and "PASSING" position, but illuminate at low-beam when the switch is at
"HEAD" position. At this position, the headlamps cannot be changed to high beam by operating the
dimmer 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."
.
TECHNICAL DESCRIPTION (COMMENT)
If the headlamps illuminate at low-beam regardless
of the lighting switch positions, the headlamp opera-
tion is in fail-safe mode.
.
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 front-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

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-307
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: "ON" to "OFF"
Lighting switch: "TAIL" or "HEAD"
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) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Operate Diagnostic Tool MB991958 according to the
procedure below to display "H/L AUTO-CUT."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "LIGHTING."
g. Select "H/L AUTO-CUT."
(4) Check that normal conditions are displayed for the items
described in the table below.
(5) When the driver's door is opened, check that normal
conditions are displayed for the items described in the table
below.
Q: Does the Diagnostic Tool MB991958 display the items
"TAILLAMP SW", "IG SW IG1", "FRONT DOOR SW" and
"H/L AUTO-CUT" as normal condition?
Normal conditions are displayed for all the items :
Replace the front-ECU. Verify that the headlamp
automatic shutdown function works normally.
Normal condition is not displayed for "TAILLAMP SW" :
Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the taillamp switch
P.54B-420."
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 ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 01 TAILLAMP SW ON
ITEM 30 IG SW (IG1) OFF
ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 32 FRONT DOOR SW ON
ITEM 35 H/L AUTO-CUT ON