Mitsubishi Lancer Evolution 7. Manual - part 281

REAR AXLE -

Troubleshooting <AYC>

27B-9

ERASING THE DIAGNOSIS CODES
Connect the MUT-II to the 16-pin diagnosis connector and

erase the diagnosis code. (Refer to GROUP 00 – How to

Use Troubleshooting/Inspection Service Points.)
Caution

Turn the ignition switch to the LOCK (OFF) position before

connecting or disconnecting the MUT-II.

INSPECTION CHART FOR DIAGNOSIS CODE

Diagnosis

code No.

Diagnosis items

Reference page

12

Power supply voltage (valve power supply) system

open- or short-circuit

Refer to

GROUP 22

13

Failsafe relay system <inside of 4WD-ECU>

open- or short-circuit

GROUP 22.

21

FR wheel speed sensor system

open- or short-circuit

22

FL wheel speed sensor system

open- or short-circuit

23

RR wheel speed sensor system

open- or short-circuit

24

RL wheel speed sensor system

open- or short-circuit

25

Wrong-diameter tire

26

Wheel speed sensor (faulty output signal)

31

Steer sensor (ST-1, ST-2, ST-N) system

open- or short-circuit

32

Steer sensor (ST-N) system

short-circuit

33

fixed

34

Steer sensor (ST-1, ST-2) system

short-circuit

or

output

fixed

41

TPS system

open-circuit or ground

42

short-circuit

45

Pressure sensor system

open-circuit or ground

46

open earth

47

abnormal power supply

51

G sensor (longitudinal) system

open- or short-circuit

52

defective sensor

56

G sensor (lateral) system

open- or short-circuit

57

defective sensor

REAR AXLE -

Troubleshooting <AYC>

27B-10

Diagnosis

code No.

Reference page

Diagnosis items

61

Stop lamp switch system

open-circuit

Refer to

GROUP 22

62

ACD mode changeover switch

stuck

GROUP 22.

63

Parking brake switch system

short-circuit or not re-

turned

65

ABS monitor system

open-circuit or defective

ABS

71

Proportioning valve <AYC> system

open- or short-circuit

27B-11

72

Directional control valve (right) system

open- or short-circuit

27B-12

73

Directional control valve (left) system

open- or short-circuit

27B-13

74

Proportioning valve <ACD> system

open- or short-circuit

Refer to

GROUP 22

81

Electric pump relay system

open- or short-circuit

GROUP 22.

82

electric pump malfunction

or pressure sensor defect

84

AYC control error

–

85

ACD control error

Refer to

GROUP 22.

NOTE

Code No.84 is not a code number output due to malfunction, but a code number output when control

for the 4WD-ECU to protect the AYC is stopped in excessive driving. AYC control can be recovered

by turning the ignition switch ON to OFF to ON.

REAR AXLE

-

Troubleshooting <AYC>

27B-11

INSPECTION PROCEDURES FOR DIAGNOSIS CODES

Code No. 71 Proportioning valve system

Probable cause

Thiscodeisoutputwhentheproportioningvalvecontrolcircuitisopen-orshort-circuited.

D

Defective proportioning valve

D

Defective harness or connector

D

Defective 4WD-ECU

<Vehicles with ACD + AYC>

NG

Check and repair the harness between

proportioning valve and body earth.

OK

Check the trouble symptom.

OK

Measure at proportioning valve con-

nector F-28.
D

Disconnect the connector and

measure at the harness side.

D

Resistance between 2 and body

earth

OK: 2 Ω or less

NG

Check the following connectors:

F-28, F-24

NG

Repair

Measure at proportioning valve con-

nector F-28.
D

Disconnect the connector and

measureattheproportioningvalve.

D

Resistance between 2 and 3

OK: 4.7 Ω or less

NG

Replace the hydraulic unit. (Refer to

P.27B-61.)

OK

Replace 4WD-ECU.

NG

Check the harness between propor-

tioning valve and 4WD-ECU.

NG

Repair

OK

Check the trouble symptom.

OK

Check the following connectors:

C-44, C-130*, C-134, F-24, F-28

NG

Repair

*: L.H. drive vehicles

<Vehicles with ACD>

OK

Replace 4WD-ECU.

OK

Check the following connector:

C-43

NG

Repair

OK

Check and repair the harness between

4WD-ECU and body earth.

Measure at 4WD-ECU connector

C-43.
D

Disconnect the connector and

measure at the harness side.

D

Resistance between 50 and body

earth

OK: 2 Ω or less

NG

Check the following connector:

C-43

NG

Repair

NG

Repair

REAR AXLE -

Troubleshooting <AYC>

27B-12

Code No. 72 Directional control valve (right) system

Probable cause

This code is output when the directional control valve (right) control circuit is open-

or short-circuited.

D

Defective directional control valve (right)

D

Defective harness or connector

D

Defective 4WD-ECU

<Vehicles with ACD + AYC>

NG

Check and repair the harness between

directional control valve (right) and

body earth.

OK

Check the trouble symptom.

OK

Replace 4WD-ECU.

NG

Checktheharnessbetweendirectional

control valve (right) and 4WD-ECU.

NG

Repair

OK

Check the trouble symptom.

OK

Check the following connectors:

C-44, C-130*, C-134, F-24, F-26

NG

Repair

OK

Measure at directional control valve

(right) connector F-26.
D

Disconnect the connector and

measure at the directional control

valve side.

D

Resistance between 1 and body

earth

OK: 2 Ω or less

NG

Check the following connectors:

F-26, F-24

NG

Repair

Measure at directional control valve

(right) connector F-26.
D

Disconnect the connector and

measure at the directional control

valve side.

D

Resistance between 1 and 2

OK: 19 - 21 Ω or less

NG

Replace the hydraulic unit. (Refer to

P.27B-61.)

*: L.H. drive vehicles

<Vehicles with ACD>

OK

Check and repair the harness between

4WD-ECU and body earth.

Measure at 4WD-ECU connector

C-43.
D

Disconnect the connector and

measure at the harness side.

D

Resistance between 50 and body

earth

OK: 2 Ω or less

NG

Check the following connector:

C-43

NG

Repair

OK

Replace 4WD-ECU.

OK

Check the following connector:

C-43

NG

Repair

NG

Repair