Mitsubishi Galant 9G. Manual — part 29

SYMPTOM PROCEDURES

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-112

INSPECTION PROCEDURE B-2: Tone Alarm: Light Reminder Tone Alarm Function does not Work
Normally.

NOTE: This troubleshooting procedure requires the
use of scan tool MB991958 and SWS monitor kit
MB991813. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor

P.54B-15

."

.

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 (LH): ON

• Taillight switch: ON

• Headlight switch: ON

The ETACS-ECU operates the light 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

• Taillights or headlights: 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

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991958: Scan 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: Probe Harness

Light Reminder Tone Alarm Function

ETACS-
ECU

· DRIVER'S DOOR SWITCH
· HEADLIGHT SWITCH
· IGNITION SWITCH (IG1)
· TAILLIGHT SWITCH

INPUT SIGNAL

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-113

STEP 1. Use scan tool MB991958 to select "ECU COMM
Check" on the SWS monitor display.
Check the following ECUs:

• ETACS-ECU

• Column switch (column-ECU)

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958. 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 special tool. Refer to "How to connect SWS

monitor

P.54B-13

."

(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Operate scan 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) Scan tool MB991958 should show "OK" on the "ECU

COMM Check" menus for both the "ETACS ECU" and the
"COLUMN ECU" menus.

Q: Is "OK" displayed for both the "ETACS ECU" and

"COLUMN ECU" menus?
"OK" is displayed for all the items : Go to Step 2.
"NG" is displayed for the "ETACS ECU" menu : Refer to

Inspection Procedure A-3 "Communication with the
ETACS-ECU is not possible

P.54B-78

."

"NG" is displayed for the "COLUMN ECU" menu : Refer

to Inspection Procedure A-2 "Communication with the
column switch (column-ECU) is not possible

P.54B-71

."

AC305411AB

MB991910

DATA LINK

CONNECTOR

MB991827

MB991824

MB991806

MB991812

AC302210

COLUMN SWITCH
CONNECTOR

COLUMN SWITCH
CONNECTOR AT
HARNESS SIDE

MB991812

AB

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-114

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 scan 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: Scan 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 scan tool MB991958 display "HEADLIGHT SW",

"TAILLIGHT 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 light 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 headlight switch

P.54B-484

."

Normal condition is not displayed for "TAILLIGHT SW" :

Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the taillight switch

P.54B-484

."

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-470

."

ITEM NO.

ITEM NAME

NORMAL CONDITION

ITEM 00

HEADLIGHT SW

Either of items is ON

ITEM 01

TAILLIGHT SW

ITEM 30

IG SW IG1

OFF

ITEM 32

FRONT DOOR SW

ON

ITEM 35

H/L AUTO-CUT

OFF

ITEM 43

BUZZER

ON

AC305411AB

MB991910

DATA LINK

CONNECTOR

MB991827

MB991824

MB991806

MB991812

AC302210

COLUMN SWITCH
CONNECTOR

COLUMN SWITCH
CONNECTOR AT
HARNESS SIDE

MB991812

AB

SYMPTOM PROCEDURES

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SIMPLIFIED WIRING SYSTEM (SWS)

54B-115

Normal condition is not displayed for "FRONT DOOR
SW" : Refer to Inspection Procedure M-4 "ETACS-ECU

does not receive any signal from the front door
switches

P.54B-477

."

Normal condition is not displayed for "H/L AUTO-CUT" :

Refer to Inspection Procedure H-9 "Headlight
automatic shutoff function does not work normally

P.54B-362

."

Normal condition is not displayed for "BUZZER" :

Replace the ETACS-ECU. The light reminder tone
alarm function should now work normally.

INSPECTION PROCEDURE B-3: Tone Alarm: Seat Belt Tone Alarm Function does not Work Normally.

NOTE: This troubleshooting procedure requires the
use of scan tool MB991958 and SWS monitor kit
MB991813. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor

P.54B-15

."

.

CIRCUIT OPERATION

The ETACS-ECU receives the driver's seat belt
switch ON signal from the ignition switch (IG1) and
the combination meter, and then controls the seat
belt tone alarm function.
The ETACS-ECU operates the seat belt tone alarm
function under the following conditions:

• Ignition switch: "ON" position

• Driver's seat belt: Unfastened

.

TECHNICAL DESCRIPTION (COMMENT)

If the seat belt tone alarm does not work, connec-
tor(s), wiring harness in the CAN bus lines, the com-
bination meter, the ETACS-ECU or the input signal
circuit may be defective.

.

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

ETACS-
ECU

·

SEAT BELT BUCKLE

SWITCH (DRIVER'S SIDE)

· IGNITION SWITCH (IG1)

COMBINATION
METER

CPU

CAN COMMUNICATION LINE
(CAN_L LINE)

CAN COMMUNICATION LINE
(CAN_H LINE)

Seat Belt Tone Alarm Function