2005 MITSUBISHI 380 ECU

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-77
STEP 5. Check the wiring harness between ETACS-ECU
connector C-218 (terminal 50), C-219 (terminal 3) and
ground.
NOTE: Also check junction block connector C-211 for loose,
corroded, or damaged terminals, or terminals pushed back in
the connector. If junction block connector C-211 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-218 (terminal 50), C-219 (terminal 3) and ground 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. The system
should communicate with the ETACS-ECU normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-78
STEP 6. Check column switch connector C-309 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is column switch connector C-309 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. The system should communicate with the
ETACS-ECU normally.
STEP 7. Check the wiring harness between column switch
connector C-309 (terminal 2) and ETACS-ECU connector
C-218 (terminal 62).
Q: Is the wiring harness between column switch connector
C-309 (terminal 2) and ETACS-ECU connector C-218
(terminal 62) in good condition?
YES : Go to Step 8.
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. The system
should communicate with the ETACS-ECU normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-79
STEP 8. Check the wiring harness between column switch
connector C-309 (terminal 3) and ETACS-ECU connector
C-218 (terminal 53).
Q: Is the wiring harness between column switch connector
C-309 (terminal 3) and ETACS-ECU connector C-218
(terminal 53) in good condition?
YES : Replace the ETACS-ECU. The system should
communicate with the ETACS-ECU normally.
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. The system
should communicate with the ETACS-ECU normally.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-80
INSPECTION PROCEDURE A-4: Communication with the Front-ECU is not Possible.
NOTE: This troubleshooting procedure requires the
use of diagnostic tool MB991958 and SWS monitor
kit MB991813. For details on how to use the SWS
monitor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The power supply to the front-ECU is provided by
the battery and the ignition switch (IG2).
If the power supply system from the battery is
defective, the system operates by the power sup-
ply from the ignition switch (IG2).
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
.
TECHNICAL DESCRIPTION (COMMENT)
It is suspected that the power supply circuit to the
front-ECU is defective, or the wiring harness
between the SWS monitor kit and the front-ECU or
their connector(s) is damaged. If the battery power
supply circuit to the ECU (terminal 5 of the
front-ECU) is damaged, also check the power supply
circuit from the ignition switch (IG2) (terminal 22 of
the front-ECU), and repair if necessary.
.
TROUBLESHOOTING HINTS
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
The front-ECU may be defective
The ETACS-ECU may be defective

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-81
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: DIAGNOSTIC 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

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-82
STEP 1. Use diagnostic tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the ETACS-ECU.
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958. Connect special tool MB991910 before con-
necting 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 diagnostic 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) DIAGNOSTIC TOOL MB991958 should show "OK" on the
"ECU COMM Check" menu for the "ETACS ECU" menu.
Q: Is "OK" displayed for the "ETACS ECU" menu?
YES : Go to Step 2.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-83
STEP 2. Check front-ECU connector A-11X for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is front-ECU connector A-11X in good condition?
YES : Go to Step 3.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. The system should communicate with the
front-ECU normally.
STEP 3. Check the battery power supply circuit to the
front-ECU. Measure the voltage at front-ECU connector
A-11X.
(1) Disconnect front-ECU connector A-11X and measure the
voltage available at the relay box side of the connector.
(2) Measure the voltage between terminal 5 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 5.
NO : Go to Step 4.

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-84
STEP 4. Check the wiring harness between front-ECU
connector A-11X (terminal 5) and the battery.
Q: Is the wiring harness between front-ECU connector
A-11X (terminal 5) and the 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. The system
should communicate with the front-ECU normally.
STEP 5. Check front-ECU connector A-12X for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is front-ECU connector A-12X in good condition?
YES : Go to Step 6.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. The system should communicate with the
front-ECU normally.
STEP 6. Check the ground circuit to the front-ECU.
Measure the resistance at front-ECU connector A-12X.
(1) Disconnect front-ECU connector A-12X and measure the
resistance available at the relay box side of the connector.
(2) Measure the resistance value between terminal 21 and
ground.
The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 8.
NO : Go to Step 7.