Mitsubishi Grandis. Manual - part 136

SPECIAL TOOLS

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-6

SPECIAL TOOLS

M1549000300764

SPECIAL TOOLS

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-7

Tool

Number

Name

Use

MB991955
A: MB991824
B: MB991827
C: MB991910
D: MB991911
E: MB991825
F: MB991826

MUT-III sub-assembly
A: Vehicle 
Communication 
Interface (V.C.I.)
B: MUT-III USB cable
C: MUT-III main 
harness A (Vehicles 
with CAN 
communication 
system)
D: MUT-III main 
harness B (Vehicles 
without CAN 
communication 
system)
E: MUT-III measure 
adapter
F: MUT-III trigger 
harness

SWS communication line check 
(ECU check and service data)

CAUTION

MUT-III main harness B 
(MB991911) should be used. 
MUT-III main harness A should 
not be used for this vehicle.

MB991910

MB991826

MB991955

MB991911

MB991824

MB991827

MB991825

A

B

C

D

E

F

DO NOT USED

TROUBLESHOOTING

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-8

TROUBLESHOOTING

PRIOR TO TROUBLESHOOTING

M1549014700486

Before carrying out troubleshooting, check the 
following two items.

• Make sure that the ETACS-ECU, the junction 

block (J/B), the front-ECU and the engine 
compartment relay box are connected securely.

MB991223
A: MB991219
B: MB991220
C: MB991221
D: MB991222

Harness set
A: Check harness
B: LED harness
C: LED harness 
adapter
D: Probe

Continuity check and voltage 
measurement at harness wire or 
connector
A: For checking connector pin 
contact pressure
B: For checking power supply 
circuit
C: For checking power supply 
circuit
D: For connecting a locally 
sourced tester

MB991813
A: MB991806
B: MB991812
C: MB991822

SWS monitor kit
A: SWS monitor 
cartridge
B: SWS monitor 
harness (for 
column-ECU)
C: Probe harness

SWS communication line check 
(ECU check and service data)

MB991529

Diagnosis code check 
harness

Input signal check by using a 
voltmeter

Tool

Number

Name

Use

MB991223

A

B

C

D

AC

B991813

A

B

C

MB991529

TROUBLESHOOTING

SMART WIRING SYSTEM (SWS) USING SWS MONITOR

54C-9

• Check that the system fuses and fusible links are 

not burned out.

STANDARD FLOW OF DIAGNOSTIC 
TROUBLESHOOTING

M1549000500672

1. Gather information about the problem from the 

customer.

2. Verify that the condition described by the 

customer exists.
NOTE: If an error occurs in the SWS 
communication line, the ECU isolated from the 
communication line performs a fail-safe or backup 
operation, so the problem may not match the one 
shown in the Trouble Symptom Chart. However, 
the cause of the failure can be tracked down by 
performing the following troubleshooting with the 
SWS monitor.

3. Confirming version number and destination

Check whether the SWS version number (0) and 
destination (EU W/O DRL) meet the vehicle 
specifications. If they are different, replace the 
ETACS-ECU with a correct one.

4. ECU check by using the SWS monitor

Check whether the communication status of the 
input- or output-signal-side ECU associated with 
the defective function is normal.

• If "OK " is displayed for all related ECUs, they 

communicate with each other normally and the 
input or output signal circuit system may be 
defective. Therefore, check SWS monitor service 
data.

• If "NG" is displayed for any of the related ECUs, 

something may be wrong with the ECU for which 
"NG" appears, its power supply or earthing 
system, or a wiring harness or connector 
between the SWS monitor and the ECU. Check 
the wiring harness and connectors associated 
with the ECU and examine the ECU itself.

5. SWS monitor data list

Select the defective function from the 
function-specific diagnostic menu, and check the 
service data that appears for each function item. 
This allows you to check whether the transmission 
data is normal or not. You can judge which circuit 
is the cause of the trouble, input circuit or output 
circuit.

AC211883

OK

OK

OK

NG

NG

NG

AB

1.

2. 

3. 

Check that the ETACS-ECU is applicable for the 

vehicle specifications. 

If the ECU is not applicable for them, 

replace it with correct one.

Check the power supply circuit for the ECU 

communication lines and repair if necessary.

4. 

5. 

7. 

6. 

Gather information about the problem 
from the customer.

Verify that the condition described 
by the customer exists.

ECU check on the SWS monitor

Confirming version number and destination

Check the data list by using the SWS monitor.

Check of output signal circuit system

Check of input signal circuit system