Mitsubishi 380. Manual - part 119

INPUT SIGNAL PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-473

DIAGNOSTIC PROCEDURE

Step 1. Pulse check
Check whether the ETACS-ECU receives signal from a trans-
mitter or not. For this check, you should use the 4-button-type 
transmitter (integrated with a key), which has already been reg-
istered.

NOTE: For how to register the keyless entry transmitter 
encrypted code, refer to GROUP 42 

− On-vehicle Service 

P.42-73

.

OK: The MUT-III sounds or the voltmeter needle fluctu-
ates.

Q: Is the check result normal?

YES : Go to Step 2.
NO :  Go to Step 4.

Step 2. Check the transmitter battery.
Refer to GROUP 42 

− Keyless entry system 

P.42-70

.

Q: Is the check result normal?

YES : Go to Step 3.
NO :  Replace the keyless entry key integrated transmitter 

battery.

Step 3. Register the encrypted code, and then retest the 
system.
(1) Register the keyless entry transmitter again.
(2) Check that each signal is received from the keyless entry 

transmitter.

Q: Is the check result normal?

YES : The trouble can be an intermittent malfunction (Refer 

to GROUP 00 

− How to Cope with Intermittent 

Malfunction 

P.00-14

).

NO :  Replace the keyless entry transmitter.

Step 4. Retest the system.
Check that each signal is received from the keyless entry key 
integrated  transmitter.

Q: Is the check result normal?

YES : The trouble can be an intermittent malfunction (Refer 

to GROUP 00 

− How to Cope with Intermittent 

Malfunction 

P.00-14

).

NO :  Replace the ETACS-ECU.

System switch

Check condition

Keyless entry transmitter 
"LOCK/UNLOCK" switch

When the switch is 
turned from off to on

Keyless entry transmitter 
"Panic" switch

When the switch is 
turned from off to on

Keyless entry transmitter 
"Trunk" switch

When the switch is 
turned from off to on

INPUT SIGNAL PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-474

INSPECTION PROCEDURE N-9: ETACS-ECU does not receive any interior lamp loaded signal.

.

CIRCUIT OPERATION

The ETACS-ECU operates the following equipment 
or functions by the interior lamp loaded signal:

• Interior lamp automatic shut-down function

• Dome lamp

• Ignition key hole illumination lamp

.

TECHNICAL DESCRIPTION (COMMENT)

If the signal is not normal, the equipment or functions 
described in "CIRCUIT OPERATION" do not work 
normally.

.

TROUBLESHOOTING HINTS

• Refer to circuit diagrams GROUP-

90

• Refer to configuration diagrams GROUP-

80

• 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

54DB014A

CONNECTOR: C-219

JUNCTION BLOCK SIDE

JUNCTION BLOCK

(REAR VIEW)

INPUT SIGNAL PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-475

DIAGNOSIS

Required Special Tool:

• MB991223: Harness Set

STEP 1. Check ETACS-ECU connector C-219 for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is ETACS-ECU connector C-219 in good condition?

YES : Go to Step 2.
NO :  Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. If the functions or equipment described in 

"CIRCUIT OPERATION" work normally, the interior 
lamp loaded signal should be normal.

STEP 2. Check the battery line of power supply circuit to 
the ETACS-ECU. Measure the voltage at ETACS-ECU 
connector C-219.
(1) Disconnect ETACS-ECU connector C-219 and measure the 

voltage available at the junction block side of the connector.

(2) Measure the voltage between terminal 20 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 4.
NO :  Go to Step 3.

54DB014A

CONNECTOR: C-219

JUNCTION BLOCK SIDE

JUNCTION BLOCK

(REAR VIEW)

54DB014A

CONNECTOR: C-219

JUNCTION BLOCK SIDE

JUNCTION BLOCK

(REAR VIEW)

AC209836

201918 171615 1413 1211 10 9 8 7 6 5 4 3 2 1

AE

CONNECTOR C-219
(JUNCTION BLOCK SIDE)

INPUT SIGNAL PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-476

STEP 3. Check the wiring harness between ETACS-ECU 
connector C-219 (terminal 20) and battery.

NOTE: Also check junction block connector C-214 for loose, 
corroded, or damaged terminals, or terminals pushed back in 
the connector. If junction block connector C-214 is damaged, 
repair or replace the damaged component(s) as described in 
GROUP 00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the wiring harness between ETACS-ECU connector 

C-219 (terminal 20) 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. If the 
functions or equipment described in "CIRCUIT 
OPERATION" work normally, the interior lamp loaded 
signal should be normal.

54DB014A

CONNECTOR: C-219

JUNCTION BLOCK SIDE

JUNCTION BLOCK

(REAR VIEW)

54DB057A

CONNECTOR: C-214

HARNESS SIDE

10

1

6

14

5

12

13

4

11

7

2

3

8

9