Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 788

LAN(diag)-61

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

LAN SYSTEM (DIAGNOSTICS)

3

CHECK DTC.
1) Turn the ignition switch to OFF.
2) Disconnect all control module connectors
(B280, B310, B136, B230, B231, B380) that are
connected to high speed CAN communication
line.
3) Connect the disconnected connectors.
4) Turn the ignition switch to ON.
5) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1223 a current malfunc-
tion?

Go to step

4.

Go to step

7.

4

CHECK HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect all control module connectors
(B280, B310, B136, B230, B231, B380) that are
connected to high speed CAN communication
line.
3) Using the tester, check for open, short
(power supply-output short, GND-output short)
in the harness.

Connector & terminal

(B40) No. 6 — (B310) No. 35:
(B40) No. 14 — (B310) No. 10:

Is harness normal?

Go to step

5.

Repair or replace
the harness.

5

CHECK DTC.
1) Connect the disconnected connectors.
2) Start the engine and stop.
3) Turn the ignition switch to ON.
4) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1223 a current malfunc-
tion?

Go to step

6.

Go to step

7.

6

CHECK DTC.
Read all DTCs using the Subaru Select Monitor.

Is U0122 displayed?

Replace the VDC/
ABS CM. <Ref. to
VDC-8,
REMOVAL, VDC
Control Module
and Hydraulic Con-
trol Unit
(VDCCM&H/U).>

Replace the body
integrated unit.
<Ref. to SL-48,
REMOVAL, Body
Integrated Unit.>

7

CHECK HARNESS.
1) Shake the harness used for CAN communi-
cation circuit.
2) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1223 a current malfunc-
tion?

Repair or replace
the harness.

Go to step

8.

8

CHECK CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect all control module connectors
(B280, B310, B136, B230, B231, B380) that are
connected to high speed CAN communication
line.

Is there connector terminal
where poor contact exists?

Repair the connec-
tor terminal where
poor contact
exists, or replace
harness.

Temporary poor
contact occurs.

Step

Check

Yes

No

LAN(diag)-62

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

LAN SYSTEM (DIAGNOSTICS)

M: DTC U1226 HIGH-SPEED CAN (DCCD) DATA IS NOT RECEIVED

DTC DETECTING CONDITION:

Not received data from DCCD CM.

TROUBLE SYMPTOM:

DCCD indicator blinks.

WIRING DIAGRAM:

CAN communication system <Ref. to WI-171, WIRING DIAGRAM, CAN Communication System.>

Step

Check

Yes

No

1

CHECK DTC.
Read all DTCs using the Subaru Select Monitor.
<Ref. to LAN(diag)-13, READ DIAGNOSTIC
TROUBLE CODE (DTC), OPERATION, Subaru
Select Monitor.>

Is there DTC U1202?

Perform the diag-
nosis according to
DTC.

Go to step

2.

2

CHECK DTC.
Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1226 a current malfunc-
tion?

Go to step

3.

Go to step

7.

2

1

B231

1

8

2

B380

B3

B9

B280

B:

6

14

B40

B380

1 2 3 4

17 18 19 20

5 6 7 8

21 22 23 24

9 10 11 12

25 26 27 28

13 14 15 16
29 30 31 32

4 5 6 7 8 9

6

2

7

2

8

2

9

2

0

3

2 3

1

1

3

2

3

3

3

4

3

5

3

6

3

0

1

1

1

4

1

5

1

6

1

7

1

8

1

9

1

7

3

8

3

9

3

0

4

2

1

3

1

1

4

2

4

3

4

4

4

5

4

6

4

0

2

1

2

3

2

4

2

2

2

5

2

B310

B231

1 2 3 4

B230

1

2

3

4

C: B136

16

10 11 12 13 14 15

25

24

30

9

8

7

17 18 19 20
28

21 22 23

29

32

31

1

2

3

4

5

6

27

26

33 34 35

B280

B:

1 2 3

4 5 6

7 8 9 10 11 12 13 14 15 16 17

18 19 20

21 22 23 24

25 26

1 2 3 4 5 6 7 8

9 10 11 12 13 14 15 16

B40

C17

C28

C: B136

B230

3

2

B310

10

35

LAN00907

SI

SI

SI

VDC CM

ECM

DCCD CM

YAW RATE &

G SENSOR

: WITH SI-DRIVE

DATA LINK

CONNECTOR

BODY

INTEGRATED

UNIT

STEERING

ANGLE

SENSOR

LAN(diag)-63

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

LAN SYSTEM (DIAGNOSTICS)

3

CHECK DTC.
1) Turn the ignition switch to OFF.
2) Disconnect all control module connectors
(B280, B310, B136, B230, B231, B380) that are
connected to high speed CAN communication
line.
3) Connect the disconnected connectors.
4) Turn the ignition switch to ON.
5) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1226 a current malfunc-
tion?

Go to step

4.

Go to step

7.

4

CHECK HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect all control module connectors
(B280, B310, B136, B230, B231, B380) that are
connected to high speed CAN communication
line.
3) Using the tester, check for open, short
(power supply-output short, GND-output short)
in the harness.

Connector & terminal

(B380) No. 18 — (B40) No. 14:
(B380) No. 2 — (B40) No. 6:

Is harness normal?

Go to step

5.

Repair or replace
the harness.

5

CHECK DTC.
1) Connect the disconnected connectors.
2) Start the engine and stop.
3) Turn the ignition switch to ON.
4) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1226 a current malfunc-
tion?

Go to step

6.

Go to step

7.

6

CHECK DCCD CM.
1) Turn the ignition switch to OFF.
2) Replace with a DCCD CM that is operating
normally.
3) Turn the ignition switch to ON.
4) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1226 a current malfunc-
tion?

Replace the body
integrated unit.
<Ref. to SL-48,
REMOVAL, Body
Integrated Unit.>

Replace the DCCD
CM. <Ref. to 6MT-
123, REMOVAL,
Driver’s Control
Center Differential
Control Module.>

7

CHECK HARNESS.
1) Shake the harness used for CAN communi-
cation circuit.
2) Read the DTC of body integrated unit using
Subaru Select Monitor.

Is U1226 a current malfunc-
tion?

Repair or replace
the harness.

Go to step

8.

8

CHECK CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect all the connector that is con-
nected to high speed CAN circuit.

Is there poor contact of connec-
tor terminal?

Repair the connec-
tor terminal where
poor contact
exists, or replace
harness.

Temporary com-
munication failure
occurs.

Step

Check

Yes

No

LAN(diag)-64

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

LAN SYSTEM (DIAGNOSTICS)

N: DTC U1300 CAN-LS MALFUNCTION

DTC DETECTING CONDITION:

Open or short in low speed CAN circuit

TROUBLE SYMPTOM:

Low speed CAN communication can not be executed normally.

WIRING DIAGRAM:

CAN communication system <Ref. to WI-171, WIRING DIAGRAM, CAN Communication System.>

Step

Check

Yes

No

1

CHECK DTC.
Read the DTC of body integrated unit using
Subaru Select Monitor. <Ref. to LAN(diag)-13,
READ DIAGNOSTIC TROUBLE CODE (DTC),
OPERATION, Subaru Select Monitor.>

Is U1300 a current malfunc-
tion?

Go to step

2.

Go to step

7.

2

*

1

*

i84

1 2

3 4

5 6

7 8

9 10 11 12

14 15 16 17 18 19 20 21 22 23

24 25

26 27 28 29

30 31 32 33

34 35

13

i88

i10

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

i77

1 2 3 4 5 6 7 8 9 10

i85

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20

2

*

2

*

2

*

2

*

1

*

1

*

1

*

1

*

11

12

AA

AA

AA

20

i85

i88

19

27

i10

26

i77

i84

1

9

LAN01360

BODY

INTEGRATED

UNIT

CAN JOINT

CONNECT

OR

COMBINATION

METER

AUDIO

: AUTO A/C

A/C

CONTROL

PANEL

: TERMINAL No. OPTIONAL ARRANGEMENT AMONG 1, 2, 3, 4 AND 5

: TERMINAL No. OPTIONAL ARRANGEMENT AMONG 6, 7, 8, 9 AND 10