Mitsubishi Galant. Manual — part 679

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-111

STEP 2. Check the input signal (by using scan tool
MB991502).
Check the input signals from the following switches:

•

Ignition switch (IG1)

•

Key reminder switch

•

Driver's side seat belt switch

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1)Connect scan tool MB991502 to the data link connector.
(2)Check that the tone alarm of scan tool MB991502 sounds

when the input signal enters.

Q: Does the tone alarm of scan tool MB991502 sound when

the input signal enters?
YES : Go to Step 4.
NO : Check the relevant input signal circuit. Refer to

P.54B-9

.

STEP 3. Check the input signal (by using a voltmeter).
Check the input signals from the following switches:

•

Ignition switch (IG1)

•

Key reminder switch

•

Driver's side seat belt switch

(1)Use special tool MB991529 to connect a voltmeter between

ground terminal 4 or 5 and ETACS-ECU terminal 9 of the
data link connector.

(2)Check that the voltmeter indicator deflects once when the

input signal enters.

Q: Does the voltmeter indicator deflect?

YES : Go to Step 4.
NO : Check the relevant input signal circuit. Refer to

P.54B-9

.

AC003081 AB

16 PIN

MB991502

AC003083

16 PIN

AB

ETACS-ECU
TERMINAL

GROUNDED TERMINAL

MB991529

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-112

STEP 4. Check the seat belt warning light circuit at the
ETACS-ECU connector C-82.
Disconnect the ETACS-ECU connector C-82 and measure at
the harness side.
(1)Connect terminal 15 to the ground.

Q: Does the seat belt warning light illuminate?

YES : Replace the ETACS-ECU. The ignition hole

illumination light should work normally.

NO : Go to Step 5.

STEP 5. Check the ignition hole illumination light bulb.

Q: Is the ignition hole illumination light bulb in good

condition?
YES : Go to Step 6.
NO : Replace it. The ignition hole illumination light should

work normally.

STEP 6. Check the key reminder switch (ignition key hole
illumination).
(1)Disconnect the key reminder switch connector C-59.
(2)Remove the ignition key hole illumination light bulb. Then

measure the resistance between the bulb terminals.

(3)Install the bulb to the key remainder switch, and then

measure the resistance between connector C-59 terminal 1
and 2. The resistance reading at this time should be much
the same as the resistance measured at Step (2).

Q: Are the two resistance values extremely different each

other?
YES : Repair or replace the key reminder switch. The

ignition key hole illumination light should work
normally.

NO (much the same) : Go to Step 7.

AC003568 AB

CONNECTOR C-82
(JUNCTION BLOCK SIDE)

AC003175 AB

CONNECTOR: C-59

COLUMN SWITCH

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-113

STEP 7. Check the key reminder switch (ignition key hole
illumination light) power supply circuit at the key reminder
switch connector C-59.
(1)Disconnect the key reminder switch connector C-59 and

measure at the harness side.

(2)Measure the voltage between terminal 2 and ground.

Q: Is the voltage approximately 12 volts (battery positive

voltage)?
YES : Go to Step 10.
NO : Go to Step 8.

STEP 8. Check the key reminder switch connector C-59 for
damage.
Q: Is key reminder switch connector C-59 in good

condition?
YES : Go to Step 9.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. The ignition key hole

illumination light should work normally.

AC003172AB

CONNECTOR C-29
(HARNESS SIDE)

AC003174 AB

CONNECTOR: C-59

COLUMN SWITCH

SWS DIAGNOSIS

TSB Revision

SIMPLIFIED WIRING SYSTEM (SWS)

54B-114

STEP 9. Check the harness wires between key reminder
switch connector C-59 and battery.

AC003174 AB

CONNECTOR: C-59

COLUMN SWITCH

AC003089AE

CONNECTOR: C-57

AC003082 AF

JUNCTION BLOCK
(FRONT VIEW)

CONNECTOR: C-78

AC003080 AB

JUNCTION BLOCK
(REAR VIEW)

CONNECTOR: C-84