Mitsubishi L200. Manual - part 788

ETACS

CHASSIS ELECTRICAL

54A-519

STEP 3. Check the diagnosis code of the engine-
ECU.
Check if the diagnosis code is set in either of the 
engine-ECU.

Q: Is the diagnosis code set?

YES : 

Diagnose the engine-ECU (Refer to 

GROUP 13A 

− Troubleshooting ). On 

completion, go to Step 5.

NO : 

Go to Step 4.

STEP 4. M.U.T.-III data list
Check the input signals below, which are related to 
the door ajar warning buzzer function.

• Turn the ignition switch to the "LOCK" (OFF) 

position.

• Open any door.

OK: Normal conditions are displayed for all 
the items.

Q: Is the check result normal?

YES <All the signals are received normally.> : 

Go 

to Step 5.

NO <The driver's door switch signal is not 
received.> : 

Refer to inspection procedure C-5 

"One of the door switch signals is not 
received  

P.54A-540

."

NO <The ignition switch (IG1) signal is not 
received.> : 

Refer to inspection procedure C-3 

"The ignition switch (IG1) signal is not 
received 

P.54A-533

."

NO <The vehicle speed signal is not received.> : 

Go to vehicle speed signal troubleshooting.

STEP 5. Retest the system.
The door ajar warning buzzer function should work 
normally.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

NO : 

Replace the ETACS-ECU and register the 
ID codes (Refer to 

P.54A-39

).

Item 
No.

Item name

Normal condition

19

Drive’s door switch

Any of them becomes 
ON.

48

Passenger’s door 
switch

49

Rear door switch

30

Ignition switch(IG1)

OFF

58

Vehicle speed signal Displays the input 

vehicle speed.

ETACS

CHASSIS ELECTRICAL

54A-520

Inspection Procedure B-4: Seat belt warning buzzer function does not work normally.

CAUTION

Whenever the ECU is replaced, ensure that the 
input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM
The ETACS-ECU operates this function in accord-
ance with the input signals below.

• Ignition switch (IG1)

• Driver's seat belt switch

• Passenger's seat belt switch

• Vehicle speed signal

If this function does not work normally, these input 
signal circuit(s) or the ETACS-ECU may be defec-
tive.

PROBABLE CAUSES

• Malfunction of the ETACS-ECU

• Malfunction of the driver's seat belt switch

• Malfunction of the passenger's seat belt switch

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ). On completion, go 

to Step 4.

STEP 2. Check the diagnosis code of the engine-
ECU.
Check if the diagnosis code is set in either of the 
engine-ECU.

Q: Is the diagnosis code set?

YES : 

Diagnose the engine-ECU (Refer to 

GROUP 13A 

− Troubleshooting ). On 

completion, go to Step 4.

NO : 

Go to Step 3.

STEP 3. M.U.T.-III data list
Check the input signals below, which are related to 
the seat belt warning buzzer function.

• Turn the ignition switch to the "ON" position.

• Remove the each inserted seatbelt.

OK: Normal conditions are displayed for all 
the items.

Q: Is the check result normal?

AC510194AB

Seat Belt Warning Buzzer Function

ETACS-
ECU

· SPEED SIGNAL

ENGINE-ECU

CAN COMMUNICATION LINE
(CAN_L LINE)

CAN COMMUNICATION LINE
(CAN_H LINE)

INPUT SIGNAL

INPUT SIGNAL

· IGNITION SWITCH (IG1)
· DRIVER'S SEAT BELT SWITCH
· PASSENGER'S SEAT BELT SWITCH

Item 
No.

Item name

Normal condition

30

Ignition switch(IG1)

ON

50

Driver’s 
seatbelt(Buckle SW)

Being turned ON 
from OFF

51

Passenger 
seatbelt(Buckle SW)

ETACS

CHASSIS ELECTRICAL

54A-521

YES <All the signals are received normally.> : 

Go 

to Step 4.

NO <The ignition switch (IG1) signal is not 
received.> : 

Refer to inspection procedure C-3 

"The ignition switch (IG1) signal is not 
received 

P.54A-533

."

NO <The seat belt switch signal is not received.> : 

Refer to inspection procedure C-6 "The seat 
belt switch signal is not received 

P.54A-544

 

<L.H. drive vehicles> or 

P.54A-544

 <R.H. 

drive vehicles>."

STEP 4. Retest the system.
The seat belt warning buzzer function should work 
normally.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

NO : 

Replace the ETACS-ECU and register the 
ID codes (Refer to 

P.54A-39

).

CHECK TROUBLE BY USING THE INPUT 
SIGNAL CHECK

M1545004900034

If a problem is found in the Service Data inspection, observe the table below.

Symptom

Inspection 
procedure 
number

Reference 
page

The column switch (lighting and wiper switch) signal is not received.

C-1

 

P.54A-523

The ignition switch (ACC) signal is not received.

C-2

 

P.54A-530

The ignition switch (IG1) signal is not received.

C-3

 

P.54A-533

The hazard warning lamp switch signal is not received.

C-4

 

P.54A-536

One of the door switch signals is not received.

C-5

 

P.54A-540

The seat belt switch signal is not received.

L.H. drive vehicles

C-6

 

P.54A-544

R.H. drive vehicles

 

P.54A-544

ETACS

CHASSIS ELECTRICAL

54A-522

INPUT SIGNAL PROCEDURES

Inspection Procedure C-1: The column switch (lighting and wiper switch) signal is not received.

CAUTION

Whenever the ECU is replaced, ensure that the 
input signal circuit is normal.

COMMENTS ON TROUBLE SYMPTOM
Input signal from the column switch is used to oper-
ate the functions below. If the signal is abnormal, 
these functions will not work normally.

• Lamp reminder function

• Turn-signal lamp operation sound function

• Headlamps

• Tail lamps

• Turn-signal lamps

• Front fog lamps

• Rear fog lamps

• Windshield wiper/washer

PROBABLE CAUSES

• Malfunction of the column switch

Wire colour code 
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue 
BR : Brown     O : Orange     GR : Grey     R : Red     P : Pink     V : Violet     PU : Purple     SI : Silver

Column Switch Power Source Circuit 

FUSIBLE 
LINK

IGNITION 
SWITCH (IG1)

20

ETACS-ECU

COLUMN 
SWITCH

COLUMN-ECU