ABS MITSUBISHI LANCER EVOLUTION IV 1998 User Guide

REAR AXLE – Troubleshooting <AYC>27-10
Code No. 26: Wheel speed sensor system (faulty output
signal)Probable cause
This code is output if the speed of one of the four wheels exceeds a specified level
when the vehicle speed is 20 km/h or more. At this time, the warning lamp is turned
on.
Defective harness or connector

Defective AYC-ECU

Defective ABS-ECU
<Vehicles with ABS>
OK
Replace ABS-ECU.
NG
Check harness between AYC-ECU
and ABS-ECU.NG
Repair
NG
Replace AYC-ECU.
OK
Check the trouble symptom.
NG
Check the following connectors:
B-24, B-95NG
Repair
OK
Check the trouble symptom.
NO
Measure at B-95 AYC-ECU connector.

Disconnect the connector and
measure at the harness side.

Ignition switch: ON

Turn tire at 1/2 to 1 revolution/sec.

Voltage across 6/7/8/9 and body
ground.
OK:42 mV or more (when mea-
sured with a circuit tester)
120 mV-P or more (when
measured with an oscillo-
scope)NGCheck the following connector:
B-95
Is ABS diagnosis code No. 15 output?YESTroubleshooting
NG
Repair
<Vehicles without ABS>
NG
Check and repair the harness between
speed sensor and AYC-ECU.
OK
Check the trouble symptom.
OK
Check the following connectors:
B-95, B-52, B-17, A-26, A-50, D-04,
D-14, D-19NG
Repair
OK
Check wheel bearing.NG
Replace
NG
Replace AYC-ECU.
OK
Check the trouble symptom.
OK
Check the following connector:
B-95NG
Repair
OK
Check speed sensor output voltage.
(Refer to P.27-31.)NGCheck speed sensor and rotor.
Check speed sensor for installation.NG
Repair
NG
Replace

REAR AXLE – Troubleshooting <AYC>27-14
Code No. 52: Longitudinal acceleration sensor systemProbable cause
This code is output when the longitudinal acceleration exceeds a predetermined value
while the vehicle is running with both ABS and brakes being inactive.
Defective longitudinal acceleration sensor

Defective harness or connector

Defective AYC-ECU
NG
Check and repair the harness between
longitudinal acceleration sensor and
AYC-ECU.
OK
Check the trouble symptom.
NG
Replace AYC-ECU.
OK
Check the trouble symptom.
OK
Check the following connector:
B-95NG
Repair
OK
Measure at B-95 AYC-ECU connector.

Connector connected

Ignition switch: ON

Voltage across 3 and body ground
OK:2.4 V to 2.6 V (where vehicle
in horizontal position)NGCheck the following connectors:
B-95, B-52, D-20
Check the acceleration sensor.
(Refer to P.27-52.)NG
Replace
NG
Repair
Code No. 61: Stop lamp switch systemProbable cause
This code is output under either of the following conditions:

Stop lamp switch remains ON for 15 min. or more.

There is an open-circuit in the harness between AYC-ECU and stop lamp switch.
Defective stop lamp switch

Defective harness or connector

Defective AYC-ECU
NG
Replace AYC-ECU.
OK
Check the trouble symptom.
OK
Check the following connector:
B-95NG
Repair
OK
Measure at the B-95 AYC-ECU con-
nector.

Disconnect the connector and
measure at the harness side.

Voltage across 11 and body ground

Brake pedal not depressed.
OK:1 V or lessNGCheck and repair the harness between
AYC-ECU and stop lamp switch.
Check the stop lamp switch.NG
Replace

REAR AXLE – Troubleshooting <AYC>27-15
Code No. 65: ABS monitor systemProbable cause
This code is output when ABS is considered to remain activated (motor relay remains
ON) for a continuous 1-min.-or-more period.
It is output also when there is an open-circuit in the harness between ABS motor
relay and AYC-ECU.
Defective harness or connector

Defective AYC-ECU
OK
Replace AYC-ECU.
NG
Check the harness between ABS
motor relay and AYC-ECU.NG
Repair
OK
Check the trouble symptom.
Is the ABS diagnosis code output?YESTroubleshooting
NO
Check the following connector:
B-95NG
Repair
Code No. 71: Proportioning valve systemProbable cause
This code is output when the proportioning valve control circuit is open- or short-circuited.
Defective proportioning valve

Defective harness or connector

Defective AYC-ECU
OK
Check and repair the harness between
proportioning valve and body ground.
OK
Check the trouble symptom.
OK
Measure at F-27 proportioning valve
connector.

Disconnect the connector and
measure at the harness side.

Continuity across 2 and body
ground
OK:ConductingNGCheck the following connectors:
F-27, F-30NG
Repair
Measure at F-27 proportioning valve
connector.

Disconnect the connector and
measure at the proportioning valve.

Resistance across 2 – 3
OK:4.7 Ω or lessNGReplace the hydraulic unit.
OK
Replace AYC-ECU.
NG
Check the harness between propor-
tioning valve and AYC-ECU.NG
Repair
OK
Check the trouble symptom.
NG
Check the following connectors:
B-96, B-94, D-06, F-30, F-27NG
Repair

REAR AXLE – Troubleshooting <AYC>27-24
7. CHECK AT AYC-ECU TERMINALS
7-1 TERMINAL VOLTAGE LISTING
(1) The voltage is to be measured across each terminal and ground terminal.
(2) Fig. below shows the arrangement of the terminals.
Terminal
No.Check itemCheck requirementNormally
1Lateral acceleration sensorIgnition switch: ON2.4 – 2.6 V
(horizontal position)
2Longitudinal acceleration
sensor ground
Lateral acceleration sensor
groundAt all times0 V
3Longitudinal acceleration
sensorIgnition switch: ON2.4 – 2.6 V
(horizontal position)
4Steer sensor (ST-2)Engine: Idle speed
Turn steering wheel slowly.0 V ↔ approx. 3 V
flashing
5Steer sensor (ST-1)Engine: Idle speed
Turn steering wheel slowly.0 V ↔ approx. 3 V
flashing
6*1FR wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
7*1FL wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
8*1RR wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
9*1FL wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
10Diagnosis selection inputBattery voltage
11Stop lamp switchIgnition switch:
ON
Stop lamp switch: ONBattery voltage
ON
Stop lamp switch: OFF1 V or less
12*1ABS monitorWhen ABS monitor is activatedBattery voltage
When ABS monitor is deactivated1 V or less
17Steer sensor (ST-N)Engine:
Idle speed
Steering wheel: Neutral position0.5 V or less
Idle speed
Steering wheel: Turned 90 from
neutral position2.5 – 3.5 V

REAR AXLE – Troubleshooting <AYC>27-25
Terminal
No.Normally Check requirement Check item
18TPSIgnition switch:
ON
Accelerator pedal: Fully closed0.3 – 1.0 V
ON
Accelerator pedal: Fully open4.5 – 5.0 V
23Diagnosis data input/output1 V or less
24Idle position switchIgnition switch:
ON
Accelerator pedal: Fully closed2 V or less
ON
Accelerator pedal: Fully open4.5 – 5.0 V
25Accumulator pressure
switchIgnition switch:
ONAccumulator internal pressure:
Low2 V or less
Accumulator internal pressure:
HighBattery voltage
26ECU groundAt all times0 V
31AYC-ECU power supplyIgnition switch: ONBattery voltage
Ignition switch: OFF0 V
35AYC motor relayIgnition switch:
ON
When motor is energizedBattery voltage
ON
When motor is deenergized2 V or less
36AYC warning lampIgnition switch:
ON
When lamp is OFFBattery voltage
ON
When lamp is ON2 V or less
37Directional control valve
(right)
Ignition switch:
ON
Right clutch: ONBattery voltage
(right)ON
Right clutch: OFF0 V
38Proportioning valveIgnition switch:
ONAYC-ON0 V to battery volt-
age
AYC-OFF0 V
39ECU backup power supplyAt all timesBattery voltage
45Directional control valve
(left)
Ignition switch:
ON
Left clutch: ONBattery voltage
(left)ON
Left clutch: OFF0 V
46ECU groundAt all times0 V
NOTE
*1: Indicates the vehicles with ABS.

REAR AXLE – Troubleshooting <AYC>27-26
7-2 LISTING OF RESISTANCE AND CONTINUITY ACROSS CONNECTOR TERMINALS ON
HARNESS SIDE
(1) Measure the resistance and check for continuity with the ignition switch in the “OFF” position and
AYC-ECU connector disconnected.
(2) Measure the resistance and check for continuity across terminals listed below.
(3) Fig. below shows the arrangement of terminals.
Terminal No.Signal nameNormally
2 – body groundLongitudinal acceleration sensor ground, lateral acceleration sensor groundConducting
26 – body groundECU groundConducting
35 – body groundAYC motor relayConducting
37 – body groundDirectional control valve (right)15.4 – 16.4 Ω
38 – body groundProportioning valve3.4 – 4.0 Ω
45 – body groundDirectional control valve (left)15.4 – 16.4 Ω
46 – body groundECU groundConducting
6 – 19*2Speed sensor (front, RH)1.4 – 1.8 Ω
7 – 20*2Speed sensor (front, LH)1.4 – 1.8 Ω
8 – 21*2Speed sensor (rear, RH)1.4 – 1.8 Ω
9 – 22*2Speed sensor (rear, LH)1.4 – 1.8 Ω
NOTE
*2: Indicates the vehicles without ABS.

REAR AXLE – On-vehicle Service <Vehicles with AYC>27-31
7. SPEED SENSOR OUTPUT VOLTAGE
MEASUREMENT <VEHICLES WITHOUT
ABS>
(1) Lift up the vehicle and release the parking brake.
(2) Disconnect the AYC-ECU harness connector and take
measurements on the harness side connector.
Caution
Insert the probe from the harness side with the double
lock of the connector unlocked. Inserting it to the
terminal side could result in poor contact.
(3) Turn the wheel to be tested at about 1/2 to one
revolution/sec. and check for the output voltage using
a circuit tester (AC mV range) or oscilloscope.
Terminal nos.
Front LHFront RHRear LHRear RH
7698
20192221
Output voltage:
When circuit tester is used: 70 mV or more
When oscilloscope is used: 200 mVp-p or more
(4) If the output voltage is lower than the above value, it
is probably attributable to the following faults. Check or
replace the speed sensor as necessary.
Excessive clearance between the pole piece and rotor
of the speed sensor
Defective speed sensor
Waveform Check Using Oscilloscope
Check the harness and connector of the speed sensor for
connection. Then, use an oscilloscope to check for output
voltage waveform of each speed sensor as follows.
Start the engine and monitor the sensor by turning the wheel;
for a driving wheel, let it turn by shifting into the 1st gear
and for a driven wheel turn it manually at a constant speed.
NOTE
(1) Waveform may be observed by actually running the
vehicle.
(2) The output voltage is low when the wheel speed remains
low and builds up as the wheel speed increases.
AYC-ECU connector harness side
When turned manually
At idle (5 to 6 km/h)
1st gear

FRONT SUSPENSION – Strut Assembly33A-4
STRUT ASSEMBLY
REMOVAL AND INSTALLATION
Post-installation Operation
Front Wheel Alignment Adjustment
(Refer to P.33A-3.)
12 3
4
5
6 7
Unit: Nm {kgfm}
44 {4.5}
108 – 127
{11.0 – 13.0}
Removal steps
1. Brake hose clamp
2. Front speed sensor bracket
<Vehicles with ABS>
3. Flange nut4. Strut tower bar
5. Plain washer
A6. Bolts
7. Strut assembly
REMOVAL SERVICE POINT
ABOLTS REMOVAL
(1) Suspend the lower arm from the vehicle with wire.
(2) Remove the strut and knuckle connection.

34-1
REAR
SUSPENSION
CONTENTS
SERVICE SPECIFICATIONS 2. . . . . . . . . . . . . .
LUBRICANT 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 2. . . . . . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE 3. . . . . . . . . . . . . . . . . .
1. Rear Wheel Alignment Check and
Adjustment 3. . . . . . . . . . . . . . . . . . . . . . . . . . .
2. Ball Joint Dust Cover Check 3. . . . . . . . . . .
REAR SUSPENSION ASSEMBLY 4. . . . . . . . . UPPER ARM ASSEMBLY 6. . . . . . . . . . . . . . . .
TRAILING ARM ASSEMBLY 8. . . . . . . . . . . . . .
LOWER ARM AND TOE CONTROL
ARM ASSEMBLIES 10. . . . . . . . . . . . . . . . . . . .
SHOCK ABSORBER ASSEMBLY 13. . . . . . .
STABILIZER BAR 14. . . . . . . . . . . . . . . . . . . . . .

REAR SUSPENSION – Rear Suspension Assembly34-4
REAR SUSPENSION ASSEMBLY
REMOVAL AND INSTALLATION
Pre-removal Operation
(1) Center Exhaust Pipe Removal
(Refer to GROUP 15.)
(2) Trunk Room Side Trim Removal <GSR>
(3) AYC Fluid Draining
(Refer to GROUP 27 – On-vehicle Service.)Post-installation Operation
(1) AYC Fluid Refilling and Bleeding
(Refer to GROUP 27 – On-vehicle Service.)
(2) Center Exhaust Pipe Installation
(Refer to GROUP 15.)
(3) AYC Operation Check
(4) Parking Brake Cable Stroke Check
(Refer to GROUP 36 – On-vehicle Service.)
(5) Wheel Alignment Check and Adjustment
(Refer to P.34-3.)
1
34
5
6
7 9 10
1112
1314
15 1617
Unit: Nm {kgf
m}
44 {4.5}
108 – 127 {11.0 – 13.0}
54 {5.5}
88 {9.0}
93 {9.5}*88 {9.0}
158 2
15
29 – 34
{3.0 – 3.5}
25 {2.6}34 {3.5}25 {2.5}
69
{7.0} Toe control bar
EVOLUTION-V RS
137 – 156 {14.0 – 16.0}*59 – 68 {6.0 – 7.0}*
Removal steps
1. Fuel filler cap
2. Bolt
3. Filler neck protector
4. Cap
5. Shock absorber mounting nut
A6. Brake caliper assembly
7. Rear speed sensor <vehicles with
AYC>
8. Brake disc
9. Parking brake cable end (Refer to
GROUP 36.)
10. AYC fluid line connection <vehicles
with AYC>BB11. Propeller shaft connection
12. Upper arm mounting bolt
13. Trailing arm mounting bolt
14. Toe control arm mounting bolt
CA15. Crossmember mounting bolt
16. Differential support assembly
mounting bolt
17. Rear suspension assembly
Caution
The parts marked with * should be first temporarily
tightened, then torqued to specification with the
vehicle on the ground in unloaded condition.