Mitsubishi Lancer Evolution VI. Manual - part 61

REAR AXLE

  – On-vehicle Service <Vehicles with AYC>

27-38

Waveform Observation Points

Symptom

Probable cause

Action

Waveform amplitude is too small, or no
waveform.

Defective wheel speed sensor

Replace sensor.

Waveform amplitude varies greatly. (No
problem if the smallest amplitude is 100

Excessive axle hub lateral and radial runout

Replace hub.

problem if the smallest amplitude is 100
mV or more)

Poor AYC-ECU grounding

Repair.

Noise on waveform or disturbed
waveform

Open-circuited sensor

Replace sensor.

waveform

Open-circuited harness

Repair harness.

Improperly mounted wheel speed sensor

Correct sensor installation.

Missing or collapsed ABS rotor tooth

Replace ABS rotor.

Caution
Since the wheel speed sensor cable follows the movement of the front or rear suspension, it
may be open-circuited only when the vehicle is run on rough roads and not on ordinary road.
The wheel speed sensor output voltage waveform should therefore be checked also by rocking
the sensor harness so that driving on rough roads may be simulated.

ACTION WHEN BATTERY RUNS OUT

When the engine is started using a booster cable where the
battery has completely run down and you attempt to start
the vehicle without waiting for the battery to recover a certain
charge, the engine can misfire and you just cannot start to
move it. In such cases, charge the battery sufficiently; or,
remove the AYC fusible link from the engine compartment
relay box to make AYC inactive before attempting to start
the vehicle. When the fusible link is removed, the AYC warning
lamp lights up. After the battery has been recharged, fit the
fusible link back again and start the engine to ensure that
the AYC warning lamp is off.

AYC fusible link

REAR AXLE

  – Hydraulic Unit <Vehicles with AYC>

27-39

HYDRAULIC UNIT <VEHICLES WITH AYC>

REMOVAL AND INSTALLATION

Caution
(1) When connecting the return hose and suction hose, do not apply lubricant.
(2) No foreign matter should be allowed in the hydraulic piping and joints.

Pre-removal Operation

D

Trunk Side Trim Removal

D

Hydraulic Piping Fluid Draining

Post-installation Operation

D

Hydraulic Piping Fluid Filling and Bleeding 
(Refer to P.27-32, 34.)

D

Trunk Side Trim Installation

1

2

3

4

5

6

7

8

9

10

11

12

13

14

12 Nm

4

12 Nm

18 Nm

12 Nm

12 Nm

18 Nm

34 Nm

34 Nm

Removal steps

1. Dust guard
2. Suction hose and return hose con-

nection

3. Hydraulic unit hose assembly con-

nection

4. Hydraulic unit and bracket assem-

bly mounting bolt

"

C

A

5. Hydraulic unit and bracket assem-

bly

A

A

"

6. Hydraulic unit

7. Hydraulic unit bracket
8. AYC harness
9. Hydraulic unit bracket

10. Hydraulic unit hose assembly

"

B

A

11. Return hose

"

B

A

12. Suction hose

"

A

A

13. Grommet
14. Oil reservoir

REAR AXLE

  – Hydraulic Unit <Vehicles with AYC>

27-40

REMOVAL SERVICE POINTS

A

A

"

HYDRAULIC UNIT REMOVAL

Should the hydraulic unit be discarded, drill a hole in the
accumulator at the illustrated position beforehand in order
to release the inside gas.

Caution
(1) The hydraulic unit has its accumulator filled with a

high pressure gas. Never throw it into a fire. Also,
never attempt to disassemble, press, weld or melt
it.

(2) When drilling a hole in the accumulator, be sure to

wear safety goggles since drill chips may blow out
together with the gas.

INSTALLATION SERVICE POINTS

"

A

A

GROMMET INSTALLATION

On the vehicle mounted with a sunroof, mount the drain pipe
to the grommet as illustrated.

"

B

A

SUCTION HOSE / RETURN HOSE INSTALLATION

Fit the suction hose and return hose to the nipple of hydraulic
unit as illustrated.

"

C

A

HYDRAULIC UNIT AND BRACKET ASSEMBLY
INSTALLATION

Hook the hydraulic unit bracket hook to the rear floor side
member and install the hydraulic unit and bracket assembly
mounting bolt.

Grommet

Drain pipe

25 

±

 5 mm

Nipple

Suction hose and
return hose

15 mm

Hook

Rear floor side member

REAR AXLE

  – Sensor Relay <Vehicles with AYC>

27-41

SENSOR RELAY <VEHICLES WITH AYC>

REMOVAL AND INSTALLATION

Caution: SRS

For vehicles with SRS, before removal of air bag module and clock spring, refer to GROUP 52B
– Service Precautions and Air Bag Module and Clock Spring.

1

2

3

4

Steer sensor removal steps

D

Steering wheel and column cover

A

A

"

1. Steer sensor

Acceleration sensor and AYC relay
removal

2. Longitudinal acceleration sensor
3. Lateral acceleration sensor
4. AYC relay

NOTE
For the wheel speed sensor, refer to GROUP 35B.

REMOVAL SERVICE POINT

A

A

"

STEER SENSOR REMOVAL

Remove the steer sensor from the column switch.

Caution
(1) A photocoupler is used as the steer sensor. Use care

not to allow dust or grease to be on the sensor.

(2) Do not bend or dirty with grease the slit plate on

the column switch side.

Slit plate

Steer sensor