Mitsubishi Grandis. Manual — part 477

SPECIAL TOOL

CONTROLLER AREA NETWORK (CAN)

54D-6

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

CAN bus diagnostics

CAUTION

For vehicles with CAN
communication, use MUT-III main
harness A to send simulated
vehicle speed. If you connect
MUT-III main harness B instead,
the CAN communication does
not function correctly.

MB991910

MB991826

MB991955

MB991911

MB991824

MB991827

MB991825

A

B

C

D

E

F

DO NOT USED

TEST EQUIPMENT

CONTROLLER AREA NETWORK (CAN)

54D-7

TEST EQUIPMENT

M1548304300076

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

MB991974

ABS check
harness

Checking continuity and measuring
voltage at ABS-ECU harness-side
connector

MB991997

ABS check
harness

Checking continuity and measuring
voltage at ASC-ECU harness-side
connector

Tool

Number

Name

Use

MB991223

A

D

C

B

AD

MB991970

MB991997

Test equipment

Name

Use

Digital multimeter

Checking CAN bus circuit (for resistance and voltage
measurements)

AC000019

SERVICE PRECAUTIONS

CONTROLLER AREA NETWORK (CAN)

54D-8

SERVICE PRECAUTIONS

M1548302100065

Warnings in diagnosis section

Details regarding warnings

When servicing an CAN bus line, earth yourself
by touching a metal object such as an unpainted
water pipe. If you fail to do, a component
connected to the CAN bus line may be broken.

−

CAUTION

A digital multimeter should be used.

When measuring resistance value or voltage in
CAN bus lines, use a digital multimeter. If not
using a digital multimeter, the equipments, which
are connected through the CAN communication
lines, may be damaged.

CAUTION

When measuring the resistance, disconnect the
negative battery terminal.

Disconnect the negative battery terminal when
measuring the resistance value in the CAN bus
line. If you fail to do so, the equipments, which
are connected through the CAN communication
lines, may be damaged.

CAUTION

The test wiring harness should be used.

Always use the test harness when measuring the
voltage or resistance value at the female
connector. If you fail to do so, connectors may be
damaged.

CAUTION

The strand end of the twist wire should be within
10 cm from the connector.

If you repair the wire due to a defective
connector or its terminal or harness wire, you
should cut the wire so that the strand end of the
twist wire should be within 10 cm from the
connector as shown. If it exceeds 10 cm, twist
the wiring harness just like the original twisted
wire. If the strand end exceeds 10 cm (4.0
inches), a communication error may be caused.

CAUTION

Strictly observe the specifed wiring harness
repair procedure.

When you repair a CAN bus line, observe the
precautions on how to repair the CAN bus line
strictly. Refer to

P.54D-9

. If a new wire is added

or a splice point is modified for the CAN_L or
CAN_H line, an error in the CAN communication
may be caused.

AC203824

CONNECTOR

TWISTED WIRE

AB

10 cm
(4.0 inches)

PRECAUTIONS ON HOW TO REPAIR THE CAN BUS LINES

CONTROLLER AREA NETWORK (CAN)

54D-9

PRECAUTIONS ON HOW TO REPAIR THE CAN BUS LINES

M1548301900079

PRECAUTIONS ON HOW TO REPAIR THE
CAN BUS LINES

• If the CAN bus line(s) are repaired, renew all the

twisted wires between the end connectors. If the
wiring harness is partially repaired, or only
CAN_L or CAN_H line is repaired, noise
suppression is deteriorated, causing a
communication error.

• If the connector or wire on the main bus line or

the sub-bus wire is replaced, the frayed end of
the twisted wire should be within 10 cm from the
connector. If it exceeds 10 cm, twist the wiring
harness just like the original twisted wire. If the
frayed end exceeds 10 cm, noise suppression is
deteriorated, causing a communication error.

• If a sub-bus line is repaired, splice a new wire

directly into the main bus line. If a new wire is
spliced into the sub-bus line, which is connected
to another device, the CAN communication will
be disabled.

PRECAUTIONS ON HOW TO REPAIR THE
TERMINATOR RESISTOR

If one-side terminator resistor is broken, the CAN
communication will continue although noise
suppression is deteriorated. No diagnosis codes may
be set even if the terminator resistor was broken. If a
damage is found, replace the ECU which
incorporates the defective terminator resistor.

EXPLANATION ABOUT THE MUT-III CAN BUS

DIAGNOSTICS

M1548300100070

The MUT-III CAN bus diagnostics carries out the
three checks below automatically, and then displays
current condition of the CAN bus lines according to
the check results.

AC204696

ADDED WIRE

NO GOOD

AB

AC203824

CONNECTOR

TWISTED WIRE

AB

10 cm
(4.0 inches)

AC202856

ECU

ECU

ECU

ECU

GOOD

NO GOOD

TERMINATOR RESISTOR

OPEN
CIRCUIT
POINT

OPEN
CIRCUIT
POINT

TERMINATOR RESISTOR

AB