Interior MITSUBISHI 380 2005 Workshop Manual
Page 1 of 1500
54B-1
GROUP 54B
SIMPLIFIED WIRING 
SYSTEM (SWS)
CONTENTS
GENERAL DESCRIPTION. . . . . . . . .54B-2
COMMUNICATION METHOD  . . . . . . . . . . 54B-2
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . 54B-2
SPECIAL TOOL . . . . . . . . . . . . . . . . .54B-8
SWS DIAGNOSIS  . . . . . . . . . . . . . . .54B-10
GENERAL DESCRIPTION . . . . . . . . . . . . . 54B-10
BEFORE CARRYING OUT 
TROUBLESHOOTING  . . . . . . . . . . . . . . . . 54B-10
DIAGNOSTIC FUNCTION  . . . . . . . . . . . . . 54B-10
SWS DIAGNOSTIC TROUBLESHOOTING 
STRATEGY . . . . . . . . . . . . . . . . . . . . . . . . . 54B-12
HOW TO CONNECT SWS MONITOR . . . . 54B-13
HOW TO CHECK ECUS . . . . . . . . . . . . . . . 54B-15
SERVICE DATA CHECK  . . . . . . . . . . . . . . 54B-15
PULSE CHECK . . . . . . . . . . . . . . . . . . . . . . 54B-24
DIAGNOSTIC TROUBLE CODE 
CHART . . . . . . . . . . . . . . . . . . . . . . . .54B-25
DIAGNOSTIC TROUBLE CODE 
PROCEDURES  . . . . . . . . . . . . . . . . .54B-25
SYMPTOM CHART  . . . . . . . . . . . . . .54B-57
INPUT SIGNAL CHART . . . . . . . . . . .54B-61
SYMPTOM PROCEDURES . . . . . . . .54B-63
TONE ALARM . . . . . . . . . . . . . . . . . . . . . . . 54B-94
GENERAL DESCRIPTION CONCERNING 
THE TONE ALARM. . . . . . . . . . . . . . . . . . . 54B-94
CENTRAL DOOR LOCKING SYSTEM. . . . 54B-118GENERAL DESCRIPTION CONCERNING 
CENTRAL DOOR LOCKING SYSTEM . . . . 54B-118
POWER WINDOWS  . . . . . . . . . . . . . . . . . . 54B-148
GENERAL DESCRIPTION CONCERNING 
THE POWER WINDOWS  . . . . . . . . . . . . . . 54B-148
KEYLESS ENTRY SYSTEM . . . . . . . . . . . . 54B-187
GENERAL DESCRIPTION CONCERNING 
THE KEYLESS ENTRY SYSTEM . . . . . . . . 54B-187
SUNROOF . . . . . . . . . . . . . . . . . . . . . . . . . . 54B-209
GENERAL DESCRIPTION CONCERNING 
THE SUNROOF  . . . . . . . . . . . . . . . . . . . . . 54B-209
WINDSHIELD WIPER AND WASHER  . . . . 54B-223
GENERAL DESCRIPTION CONCERNING 
THE WINDSHIELD WIPER AND WASHER  54B-223
HEADLAMP AND TAILLAMP  . . . . . . . . . . . 54B-257
GENERAL DESCRIPTION CONCERNING 
THE HEADLAMPS AND TAILLAMPS . . . . . 54B-257
FLASHER TIMER  . . . . . . . . . . . . . . . . . . . . 54B-309
GENERAL DESCRIPTION CONCERNING 
THE FLASHER TIMER  . . . . . . . . . . . . . . . . 54B-309
FOG LAMP  . . . . . . . . . . . . . . . . . . . . . . . . . 54B-339
GENERAL DESCRIPTION CONCERNING 
THE FOG LAMPS . . . . . . . . . . . . . . . . . . . . 54B-339
INTERIOR LAMP . . . . . . . . . . . . . . . . . . . . . 54B-355
GENERAL DESCRIPTION CONCERNING 
THE INTERIOR LAMP  . . . . . . . . . . . . . . . . 54B-355
INPUT SIGNAL PROCEDURES . . . . .54B-405
CHECK AT ECU TERMINAL  . . . . . . .54B-480
ON-VEHICLE SERVICE . . . . . . . . . . .54B-486
CONFIGURATION FUNCTION . . . . . . . . . . 54B-486 
Page 6 of 1500
GENERAL DESCRIPTION
SIMPLIFIED WIRING SYSTEM (SWS)54B-6
FOG LAMP
.
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 
shutdown 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 while the 
tail lamps are on 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 illuminate 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.
INTERIOR LAMP
ETACS-ECU makes it possible to force operation of 
all ON and OFF lamp switches in the overhead con-
sole (the dome lamp, reading lamp, cargo area lamp, 
rear personal lamps, front door lamps, and front foot 
lamps). This function is assigned higher priority than 
the controls for the interior lamp switch that are per-
formed when the doors are in certain positions.
When the lamps are forced on, the illumination 
level is 100% as all interior lamps are switched on 
(the dome lamp, reading lamp, cargo area lamp, 
rear personal lamps, front door lamps, and front 
foot lamps). Even when all lamps are forced on, 
the interior lamp automatic shutoff function is 
active.
When the lamps are forced off, all interior lamps 
are immediately switched off (the dome lamp, 
reading lamp, cargo area lamp, rear personal 
lamps, front door lamps, and front foot lamps).When the interior lamp switch is at DOOR position, 
the ETACS-ECU controls the interior lamps as fol-
lows:
When a door is opened with the ignition switch 
off, the interior lamps up to a luminance of 100 
percent. When a door is closed, the interior lamps 
dims a luminance of 65 percent, and goes off 30 
seconds later. However, if the ignition switch is 
turned ON or if a door is locked while the interior 
lamps is dimming, the dome lamp will go off at 
that point.
When a door is opened with the ignition switch 
ON, the interior lamps up at a luminance of 100 
percent. When all doors are closed, the interior 
lamps go off.
When the ignition key is removed with all doors 
closed, the interior lamps up at a luminance of 
100 percent, and goes off 30 seconds later. How-
ever, if the ignition key is inserted again or if a 
door is locked while the interior lamps is lighting, 
the interior lamps will go off at that point.
To check keyless entry operations more easily, 
the interior lamps will flash twice when doors are 
locked. When doors are unlocked, the interior 
lamps up at a luminance of 100 percent, and 
goes off 15 seconds later.
INTERIOR LAMP AUTOMATIC 
SHUTDOUN FUNCTION
Illuminated interior lamps such as the front dome 
lamp, etc. (all lamps using the dome lamp fuse as the 
power supply) will automatically go off in the follow-
ing conditions to prevent the battery from discharging 
as a result of forgetting to turn off the lamps or 
incomplete closing of the door.
When the ignition switch is turned off and more 
than 30 minutes pass by with the interior lamp 
illuminated, the interior lamps will go off automati-
cally.
When the ignition switch is turned off and one of 
the door switches remains open for 30 minutes 
continuously, the interior lamps will go off auto-
matically. 
Page 7 of 1500
GENERAL DESCRIPTION
SIMPLIFIED WIRING SYSTEM (SWS)54B-7
SEAT BELT INDICATOR
If any of the following conditions is met with the igni-
tion switch at "ON" or "ST", the ETACS-ECU illumi-
nates, flashes or extinguishes the seat belt indicator 
by using the driver's seat belt switch signal and the 
vehicle speed signal sent from the combination 
meter.
Illuminates when the ignition switch is at "ON" 
and the seat belt switch is turned on (the driver's 
seat belt is unfastened).
Flashes and illuminates the indicator 12 cycles 
(after 0.5 seconds) if any of the following condi-
tions is met when sixty seconds or more have 
elapsed since the ignition switch is turned "ON". 
One cycle consists of five-second "flashing" and 
then three-second "illumination".
a. The vehicle speed has reached 8 km/h (5 
mph) while the seat belt switch is turned on 
(driver's seat belt is not fastened) with the 
ignition switch "ON.
b. The seat belt switch has been turned on 
(driver's seat belt has not been fastened) for 
at least ten seconds while the ignition switch 
has been turned "ON" and the vehicle speed 
has been 8 km/h (5 mph) or more.
NOTE: Once this timer operation has been acti-
vated, it will not be activated again until the 
vehicle speed reduces to 3 km/h (2 mph) or 
less even if any of the following conditions is 
met.
The indicator stops illuminating if the ignition 
switch or the seat belt switch is turned off (the 
driver's seat belt is fastened) while the timer 
operation is active. 
DOOR-AJAR INDICATOR LAMP
The combination meter receives the signal sent from 
the ETACS-ECU about whether each door or trunk is 
open or closed and turns the door ajar indicator lamp 
on and off. While the door ajar indicator is illumi-
nated, the door ajar warning function is activated and 
the door ajar indicator lamp flashes 4 times. If the 
door remains open even after the 4 warning flashes, 
the door ajar indicator lamp will be illuminated again.
CONFIGURATION FUNCTION
The following functions can be adjusted by operating 
the middle-grade multi center display (if equipped).
Keyless entry horn answerback function
Keyless entry hazard lamp answerback function
Timed locking mechanism
Turn-signal lamp buzzer
Door ajar warning buzzer
Adjustment of door unlocking operation on key-
less entry system
Vehicle speed-dependent wiper function
Headlamp automatic shutdown function
Delay-off time of the dome lamp
Interior lamp automatic shutoff function
Initialisation of above mentioned functions 
Page 24 of 1500
SWS DIAGNOSIS
SIMPLIFIED WIRING SYSTEM (SWS)54B-24
SUNROOF
PULSE CHECK
M1549015100562
1. The input signals (signals other than SWS 
communication line signals), which are 
compatible with the SWS monitor by using the 
diagnostic tool MB991958 (MUT-III Sub 
Assembly) or voltmeter, can be confirmed by the 
Pulse Check.2. Use the diagnostic tool MB991958 (MUT-III Sub 
Assembly) or voltmeter to check the following 
input signals.
NOTE:  If a problem is found in the Pulse Check, 
refer to Input Signal Chart P.54B-61.
Switches and their conditions, which are applicable 
for Pulse CheckITEM ITEM NO. INPUT SIGNAL DISPLAY ON 
DIAGNOSTIC TOOLNORMAL CONDITION
SUNROOF 
OPE.30 Ignition switch 
(IG1)IG SW (IG1) (ETACS ECU) ON
72 Response by the 
sunroof-ECUS/R ECU ACK (SUNROOF 
ECU)INPUT CHECK (only 
momentarily when switch is 
operated)
INPUT SIGNAL REQUIREMENTS FOR SOUNDING TONE 
ALARM
Key reminder switch When the ignition key is pulled out
Hazard warning lamp switch When the switch is turned from off to on
Door switches A door is opened when all the doors are 
closed
Door lock key cylinder switch When a door is locked or unlocked by a key 
cylinder
Door lock actuators Move the door lock knob from lock position 
to unlock position or vice versa
Door lock switch (incorporated in the power window main 
switch and front power window sub switch)When a door is locked or unlocked by a door 
lock switch
Keyless entry transmitter When the switch is turned from off to on
Interior lamp loaded signal Illuminates the interior lamps 
Page 60 of 1500
SYMPTOM CHART
SIMPLIFIED WIRING SYSTEM (SWS)54B-60
Interior lamp General description concerning the interior lampP.54B-355
The dome lamp do not illuminate and go out 
normally.K-1
P.54B-359
The front dome lamp, rear dome lamp or trunk 
lamp do not illuminate or go out normally.K-2
P.54B-366
Dome lamp dimming function does not work 
normally.K-3
P.54B-376
The ignition key hole illumination lamp does not 
illuminate or go out normally.K-4
P.54B-381
The interior lamp automatic shutoff function does 
not work normally.K-5
P.54B-389
The door ajar indicator lamps do not illuminate or 
go out normallyK-6
P.54B-394
The seat belt warning lamp do not illuminate or go 
out normallyK-7
P.54B-398
Can not customize the functions by operating the multi center display . L-1
P.54B-402 SYSTEM SYMPTOM INSPECTION 
PROCEDUREREFERENCE 
PA G E 
Page 62 of 1500
INPUT SIGNAL CHART
SIMPLIFIED WIRING SYSTEM (SWS)54B-62
DIAGNOSTIC TOOL OR VOLTMETER
If a problem is found in the Pulse Check, observe the 
table below.
SYMPTOM INSPECTION 
PROCEDUREREFERENCE 
PA G E
ETACS-ECU does not receive any signal from the key reminder switch. N-1
P.54B-432
ETACS-ECU does not receive any signal from the hazard warning lamp 
switch.N-2
P.54B-436
ETACS-ECU does not receive any signal from any of the door switches. N-3
P.54B-440
ETACS-ECU does not receive any signal from the door lock key cylinder 
switch.N-4
P.54B-446
ETACS-ECU does not receive any signal from the front door lock actuator. N-5
P.54B-451
ETACS-ECU does not receive any signal from the door lock switch 
(incorporated in the power window main switch and front power window 
sub switch).N-6
P.54B-460
ETACS-ECU does not receive any signal from the trunk lid latch assembly. N-7
P.54B-469
Transmitter ETACS-ECU does not receive any signal from the lock, 
unlock, trunk or panic switch.N-8
P.54B-472
ETACS-ECU does not receive any interior lamp loaded signal. N-9
P.54B-474 
Page 355 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-355
54B
INTERIOR LAMP
GENERAL DESCRIPTION CONCERNING THE INTERIOR LAMPM1549021800236
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80The following ECUs affect the functions and control 
of the interior lamps.
Interior lamp control function
The ETACS-ECU controls the interior lamps by turn-
ing them on and off in the following way:
When a door is opened with the ignition switch 
off, the interior lamps up to a luminance of 100 
percent. When a door is closed, the interior lamps 
dims at a luminance of 65 percent, and goes off 
30 seconds later. However if the ignition switch is 
turned ON or if a door is locked while the interior 
lamps is dimming, the dome lamp will go off at 
that point.
When a door is opened with the ignition switch 
ON, the interior lamps up at a luminance of 100 
percent. When a door is closed, the interior lamps 
go off.
When the ignition key is removed with all doors 
closed, the interior lamps up at a luminance of 
100 percent, and goes off 30 seconds later. How-
ever if the ignition key is inserted again or if a 
door is locked while the interior lamps is lighting, 
the interior lamps will go off at that point.
To check keyless entry operations more easily, 
the interior lamps is flashed once when the doors 
are locked. When the doors are unlocked, the 
interior lamps at a luminance of 100 percent, and 
go off 15 seconds later.
NOTE: The dimmer function can be customised on 
vehicles equipped with a multi center display (middle 
grade type).  Refer to P.54B-486.
NOTE: The dotted lines indicate that lighting mode 
when the ignition switch is turned ON, door is locked, 
or any door is opened during the timer illumination 
time. FUNCTION CONTROL ECU
Interior lamp control function ETACS-ECU
Interior lamp automatic-shutoff function ETACS-ECU
Ignition key hole illumination lamp function ETACS-ECU
Door ajar indicator ETACS-ECU
Seat belt indicator ETACS-ECU 
Page 356 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-356
Interior lamp automatic-shutoff function
Illuminated interior lamps such as the front dome 
lamp, etc. (all lamps using the dome lamp fuse as the 
power supply) will automatically go off in the follow-
ing conditions to prevent the battery from discharging 
as a result of forgetting to turn off the lamps or 
incomplete closing of the door.
When the ignition switch is turned off and more 
than 30 minutes pass with the interior lamp illumi-
nated, the interior lamps will go off automatically.
When the ignition switch is turned off and one of 
the door switches remains open for 30 minutes 
continuously, the interior lamps will go off auto-
matically.
NOTE: The interior lamp automatic shutoff function 
can be customised on vehicles equipped with a multi 
center display (middle grade type).  Refer to 
P.54B-486.
Ignition key hole illumination lamp function
The ignition key hole illumination lamp illuminates when the 
driver's door is opened with the ignition switch off, and for 30 
seconds after the driver's door is closed. It also illuminates for 
30 seconds after the ignition key is pulled out. In any case, it 
goes out when the ignition switch is turned on.
Door ajar indicator
The combination meter receives the signal sent from the 
ETACS-ECU about whether each door is open or closed and 
turns the door ajar indicator on and off. While the door ajar indi-
cator is illuminated, the door ajar warning function is activated 
and the door ajar indicator flashes 4 times. If the door remains 
open even after the 4 warning flashes, the door ajar indicator 
will be illuminated again. And when the interior lamp auto-
matic-shutoff function is activated, the door ajar indicator is 
extinguished. 
Page 359 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-359
INSPECTION PROCEDURE K-1: Interior Light: The dome lamp do not illuminate and go out 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 dome lamp according 
to the following signals:
Ignition switch (IG1): ON or OFF
Key reminder switch: ON or OFF
Door switches: ON or OFF
Driver’s door lock actuator switch: ON or OFF
Interior lamp loaded signal: ON
.
TECHNICAL DESCRIPTION (COMMENT)
If the dome lamp does not illuminate normally, a 
burned-out dome lamp bulb, the input circuits from 
the switches described in "CIRCUIT OPERATION", 
the power supply line to the switches 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 ETACS-ECU may be defective 
Page 363 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-363
STEP 3. Check the input signal (by using the pulse check 
mode of the monitor).
Check the following switches and input signals:
Key reminder switch
Interior lamp loaded signal
Door switches
(1) Operate diagnostic tool MB991958 according to the 
procedure below to display "Pulse check."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "Pulse Checking."
(2) Check if diagnostic tool MB991958 sounds or not.
Q: When the key reminder switch, any door switch or 
interior lamp is operated, does diagnostic tool 
MB991958 sound?
Buzzer of diagnostic tool MB991958 sounds normally. : 
Go to Step 4.
Diagnostic tool MB991958 does not sound when the 
ignition key is removed and reinserted : Refer to 
Inspection Procedure N-1 "ETACS-ECU does not 
receive any signal from the key reminder switch 
P.54B-432."
When one of the interior lamps is illuminated, 
diagnostic tool MB991958 does not sound : Refer to 
Inspection Procedure N-9 "ETACS-ECU does not 
receive any interior lamp loaded signal P.54B-474."
When one of the doors is opened and closed, 
diagnostic tool MB991958 does not sound : Refer to 
Inspection Procedure N-3 "ETACS-ECU does not 
receive any signal from any of the door switches 
P.54B-440." ITEM NAME CONDITION
key reminder switch Remove and reinsert the ignition 
key
interior lamp loaded 
signalTurn on one of the interior lamps
door switches Open or close one of the doors