Mitsubishi Outlander XL. Manual — part 1132

ZC5017890000

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(h)

(d)

(e)

(f)

(g)

ETACS-ECU
(Gateway)

Reference circuit

Data link
connector

ECU which
cannot
communicat
e with the
scan tool

Possible
trouble
spot

Logic for narrowing down trouble spot

ETACS-ECU
and all ECUs

CAN bus line
(h)

and

power
supply
system

to

ETACS-
ECU

The ETACS-ECU and the
other ECUs use the CAN bus
line

(h)

when

they

communicate with scan tool
MB991958. Since none of the
ETACS-ECU and the other
ECUs can communicate with
scan tool MB991958, CAN
bus line (h) or the power
supply circuit to the ETACS-
ECU may be faulty.

ZC501790000

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

CONTROLLER AREA NETWORK (CAN)

54D-11

EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III) CAN BUS DIAGNOSTICS

ECU which
cannot
communicat
e with the
scan tool

Possible
trouble
spot

Logic for narrowing down trouble spot

ECU A

CAN bus line
(a)

and

power
supply
system

to

ECU A

ECU A communicates with
the scan tool MB991958 via
CAN bus lines (a) and (b).
Scan tool MB991958 judges
that CAN bus line (b) is
normal, because it can
communicate

with

other

ECUs. Possible trouble may
be present in CAN bus line (a)
or the power supply system to
ECU A.

ZC501790001

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

ECU C

CAN bus line
(g)

and

power
supply
system

to

ECU C

The ECU C communicates
with scan tool MB991958 via
CAN bus lines (b), (c), (d) and
(g). Scan tool MB991958
judges that CAN bus lines (b),
(c) and (d) are normal,
because it can communicate
with ECUs B and D. Possible
trouble may be present in
CAN bus line (g) or the power
supply system to ECU C.
ECU C communicates with
scan tool MB991958 via CAN
bus lines (b), (c), (d) and (g).
Scan tool MB991958 judges
that CAN bus lines (b), (c)
and (d) are normal, because
it can communicate with
ECUs B and D. Possible
trouble may be present in
CAN bus line (g) or the power
supply system to ECU C.

ZC501790002

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

54D-12

CONTROLLER AREA NETWORK (CAN)

EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III) CAN BUS DIAGNOSTICS

ECU which
cannot
communicat
e with the
scan tool

Possible
trouble
spot

Logic for narrowing down trouble spot

ECU C and
ECU D

Trouble

in

CAN bus line
(d)

ECUs C and D communicate
with scan tool MB991958 via
CAN bus lines (b), (c), (d), (e)
and (g). Scan tool MB991958
judges that CAN bus lines (b)
and (c) are normal, because
it can communicate with ECU
B. Possible trouble may be
present in CAN bus line (d),
(e) or (g) or the power supply
system to ECU C and ECU D.
CAN bus line (d) is shared by
ECUs C and D when they
communicate with scan tool
MB991958, so CAN bus line
(d) is suspected as ultimate
cause. CAN bus line (g) or (e)
and power supply systems to
ECU C or D are also
suspected as second cause.

ZC501790003

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

ECU B and
ECU D

CAN bus line
(e) or (f) or
power
supply
system

to

ECU B or D

ECUs C and D communicate
with scan tool MB991958 via
CAN bus lines (b), (c), (d), (e)
and (f). Scan tool MB991958
judges that CAN bus lines (b),
(c) and (f) are normal,
because it can communicate
with ECU C. Possible trouble
may be present in CAN bus
line (f) or (e) or the power
supply system to ECU D.

ZC501790004

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

All

ECU

(except
ETACS-
ECU)

CAN bus line
(b)

The other ECUs except the
ETACS-ECU use CAN bus
lines (b) and (h) when they
communicate with scan tool
MB991958. It must be
assumed that CAN bus line
(b) is defective since the
ETACS-ECU

can

communicate with scan tool
MB991958.

ZC501790005

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

2.

Pinpoint possible trouble spot according to diagnostic trouble code

CONTROLLER AREA NETWORK (CAN)

54D-13

EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III) CAN BUS DIAGNOSTICS

If diagnostic trouble code related to CAN communication is set as past trouble, isolate opens as described
below.

NOTE:

If you pinpoint trouble spot according to diagnostic trouble code, you should use time-out

diagnostic trouble code. Diagnostic trouble code related to failure information is set when the data
to be set contains an error, so CAN bus line itself is probably normal.

NOTE:

Time-out diagnostic trouble codes are stored in each ECU memory individually. Therefore, it

is possible that these diagnostic trouble codes have not been set simultaneously. If the trouble
spot cannot be found when you diagnose by judging from multiple diagnostic trouble codes, check the
communication lines between each ECU.

Diagnostic
trouble code to
be set

Possible
trouble spot

Logic for narrowing down trouble spot

Time-out
diagnostic
trouble

code

associated with
ECU D is stored
in ECU A, ECU
B and ECU C.

Trouble

in

CAN bus line
(e)

and

power supply
system

to

ECU D

When time-out diagnostic
trouble code associated
with ECU D is stored in
ECU A, B and C, or time-out
diagnostic trouble code
associated with ECUs A, B
and C is stored in ECU D,
or "bus off" diagnostic
trouble code is stored in
ECU D, CAN bus line (e) is
suspected.

When

diagnostic trouble code is
not stored in ECU D, the
power supply to ECU D is
suspected.

ZC501790006

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

Time-out
diagnostic
trouble

code

associated with
ECUs A, B and
C is stored in
ECU D.
"Bus

off"

diagnostic
trouble code is
stored in ECU
D.
Time-out
diagnostic
trouble

code

associated with
ECU A is stored
in ECUs B, C
and D.

Trouble

in

CAN bus line
(a)

and

power supply
system

to

ECU A.

When time-out diagnostic
trouble code associated
with ECU A is stored in
ECUs B, C and D, or time-
out diagnostic trouble code
associated with ECUs B, C
and D is stored in ECU A,
or "bus off" diagnostic
trouble code is stored in
ECU A, CAN bus line (a) or
(c) is suspected. When
diagnostic trouble code is
not stored in ECU A, the
power supply to ECU A is
suspected.

ZC501790007

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

ETACS-ECU
(Gateway)

Data link
connector

Time-out
diagnostic
trouble

code

associated with
ECUs B, C and
D is stored in
ECU A.

54D-14

CONTROLLER AREA NETWORK (CAN)

EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III) CAN BUS DIAGNOSTICS