Mitsubishi 380. Manual - part 97

SYMPTOM PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-385

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

(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) When the switches (see table below), which are applicable 

for the input signal check, are operated, check if diagnostic 
tool MB991958 sounds or not.

Q: When the key reminder switch and the interior lamp are 

operated, does diagnostic tool MB991958 sound in each 
case?
Buzzer of diagnostic tool MB991958 sounds normally. : 

Go to Step 4.

When the ignition key is removed and reinserted, 
diagnostic tool MB991958 does not sound : 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

."

STEP 4. Check ETACS-ECU connector C-218 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is ETACS-ECU connector C-218 in good condition?

YES : Go to Step 5.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Verify that the ignition key hole illumination 

lamp illuminates normally.

ITEM NAME

CONDITION

key reminder switch

Remove and reinsert the 
ignition key

interior lamp loaded signal

Turn on one of the interior 
lamps

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

54DB006A

CONNECTORS: C-218

JUNCTION BLOCK
(REAR VIEW)

C-218 (GR)

HARNESS SIDE

45

46

48 47

49

50
59

51
60

52

53
62

65

61

54
63

56

68

64

67 66

57

58

55

SYMPTOM PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-386

STEP 5. Check at ETACS-ECU connector C-218 in order to 
check the ignition key hole illumination lamp circuit.
(1) Disconnect ETACS-ECU connector C-218, and measure at 

the wiring harness side.

(2) The ignition key hole illumination lamp should illuminate 

when terminal 63 is grounded.

Q: Does the ignition key hole illumination lamp illuminate?

YES : Replace the ETACS-ECU. Verify that the ignition key 

hole illumination lamp illuminates normally.

NO :  Go to Step 6.

STEP 6. Check key reminder switch connector C-310 for 
loose, corroded or damaged terminals, or terminals 
pushed back in the connector.
Q: Is key reminder switch connector C-310 in good 

condition?
YES : Go to Step 7.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Verify that the ignition key hole illumination 

lamp illuminates normally.

STEP 7. Check the ignition key hole illumination lamp 
bulb.

Q: Is the ignition key hole illumination lamp bulb in good 

condition?
YES : Go to Step 8.
NO :  Replace the bulb. Verify that the ignition key hole 

illumination lamp illuminates normally.

54DB006A

CONNECTORS: C-218

JUNCTION BLOCK
(REAR VIEW)

C-218 (GR)

HARNESS SIDE

45

46

48 47

49

50
59

51
60

52

53
62

65

61

54
63

56

68

64

67 66

57

58

55

16DB456A

CONNECTOR C-218
(HARNESS SIDE)

54DB004A

CONNECTOR: C-310

HARNESS SIDE

SYMPTOM PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-387

STEP 8. Check the key reminder switch (ignition key hole 
illumination).
(1) Disconnect key reminder switch connector C-310.
(2) Remove the ignition key hole illumination lamp bulb. Then 

measure the resistance value between the bulb terminals.

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

resistance between connector C-310 terminals 1 and 2. The 
measured resistance value should be roughly the same as 
the value measured in Step (2).

Q: Are these two resistance values extremely different?

YES : Replace the key reminder switch. Verify that the 

ignition key hole illumination lamp illuminates 
normally.

NO :  <Nearly equal> Go to Step 9.

STEP 9. Check the battery power supply circuit to the key 
reminder switch circuit. Measure the voltage at key 
reminder switch connector C-310.
(1) Disconnect key reminder switch connector C-310, and 

measure the voltage available at the wiring harness side of 
the connector.

(2) Measure the voltage 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 11.
NO :  Go to Step 10.

54DB004A

CONNECTOR: C-310

HARNESS SIDE

54DB004A

CONNECTOR: C-310

HARNESS SIDE

AC209364

CONNECTOR C-310
(HARNESS SIDE)

GY

SYMPTOM PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-388

STEP 10. Check the wiring harness between key reminder 
switch connector C-310 (terminal 2) and battery.

NOTE: Also check intermediate connector C-29 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the 
connector. If intermediate connector C-29 is damaged, repair or 
replace the connector as described in GROUP 00E, Harness 
Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between key reminder switch 

connector C-310 (terminal 2) and 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 ignition key hole illumination lamp illuminates 
normally.

54DB004A

CONNECTOR: C-310

HARNESS SIDE

25DB113A

CONNECTOR: C-29