Mitsubishi Lancer Evolution IX. Manual — part 514

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-87

INSPECTION PROCEDURE 2: Communication between the M.U.T.-II/III and the ABS-ECU is not
possible.

ABS-ECU

DIAGNOSIS
CONNECTOR

FRONT SIDE

IGNITION
SWITCH (IG2)

POWER
SUPPLY

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Gray R : Red P : Pink V : Violet

ABS-ECU Power Supply /Earth and Diagnosis Connector Circuit

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-88

OPERATION

• The diagnosis code is set by the ABS-ECU (ter-

minal 2) to the diagnostic output terminal (termi-
nal 7) of the diagnosis connector.

• When the diagnosis connector's diagnosis test

mode control terminal (terminal 1) is earthed, the
ABS-ECU will go into diagnosis mode.

COMMENT ON TROUBLE SYMPTOM

When communication with the M.U.T.-II/III is not pos-
sible, the cause is probably an open circuit in the
ABS-ECU power circuit or an open circuit in the diag-
nostic output circuit.

PROBABLE CAUSES

The most likely causes for this case are:

• Blown fuse

• Damaged wiring harness or connector

• Malfunction of the brake modulator hydraulic unit

(Integrated with ABS-ECU)

DIAGNOSIS

STEP 1. Check the power supply circuit. Voltage
measurement at ABS-ECU connector B-118.

(1) Disconnect ABS-ECU connector B-118 and

measure at the harness side.

(2) Start the engine.
(3) Measure the voltage between terminal 10 and

earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Go to Step 2.

AC212153

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Connector B-118
(harness side)

AC

B-118 (B)

Connector: B-118

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-89

STEP 2. Check the following connectors.

•

ABS-ECU connector B-118

•

Junction block connectors C-210, C-211

•

Intermediate connector C-124
Check the connectors for loose, corroded or dam-
aged terminals, or terminals pushed back in the con-
nector.

Q: Are the connectors and terminals in good

condition?
YES :

Go to Step 3.

NO :

Repair it and then go to Step 9.

STEP 3. Check the following harness wire.

The wire between junction block connector C-211
(terminal 2) and ABS-ECU connector B-118 (terminal
10)

Q: Is the harness wire damaged?

YES :

Repair or replace it and then go to Step 9.

NO :

Go to Step 9.

AC211901AD

B-118 (B)

Connector: B-118

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Harness side

AC212152

Connectors: C-210, C-211

C-210

C-211

AC

Junction block
(Front view)

Connector C-210
(Harness side)

4

6 5

3

2

1

10

1

6

14

5

12

13

4

11

7

2

3

8

9

Connector C-211
(Harness side)

AC211265

Connector: C-124

AR

18

3

16

15

14

1 2

17

4 5

8

20

19

6 7

2122

9 10

25

13

24

23

12

11

AC211269

Connector: C-211

AL

Junction block
(Front view)

Harness side

4

6 5

3

2

1

AC211901AD

B-118 (B)

Connector: B-118

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Harness side

TROUBLESHOOTING

ANTI-SKID BRAKING SYSTEM (ABS)

35B-90

STEP 4. Check the earth circuit. Resistance
measurement at ABS-ECU connector B-118.

Measure the resistance between terminal 12 and
earth, and terminal 34 and earth.

OK: 2 ohms or less

Q: Is the resistance 2 ohms or less?

YES :

Go to Step 7.

NO :

Go to Step 5.

STEP 5. Check the following connector.

•

ABS-ECU connector B-118
Check the connector, for loose, corroded or dam-
aged terminals, or terminals pushed back in the con-
nector.

Q: Are the connector and terminals in good

condition?
YES :

Go to Step 6.

NO :

Repair it and then go to Step 9.

STEP 6. Check the following harness wires.

•

The wire between ABS-ECU connector B-118 (termi-

nal 12) and earth (No.14)

• The wire between ABS-ECU connector B-118

(terminal 34) and earth (No.14)

Q: Is any harness wire damaged?

YES :

Repair or replace it and then go to Step 9.

NO :

Go to Step 9.

AC212153

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Connector B-118
(harness side)

AE

B-118 (B)

Connector: B-118

AC211901AD

B-118 (B)

Connector: B-118

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Harness side

AC211901AD

B-118 (B)

Connector: B-118

28

32

34

12

11

33

30

21

9

10

22

31

7

8

29

20 19

24

2

26

4

5

6

27

18 17

3

25

16 15

1

23

13

14

Harness side

AC211898AC

Earth

NO.14