1999 MITSUBISHI LANCER EVOLUTION VI lamp

MPI – Troubleshooting13-65
Terminal
No.Normal condition Check condition (Engine condition) Check item
41Alternator FR terminal
Engine: Warm, idle (radiator fan: OFF)

Headlamp: OFF to ON

Brake lamp: OFF to ON

Rear defogger switch: OFF to ONVoltage drops by 0.2 –
3.5 V.
45A/C switchEngine: Idle speedTurn the A/C switch OFF0 – 3 V
Turn the A/C switch ON
(A/C compressor is oper-
ating)System voltage
60Oxygen sensor heater

Engine: Idling0 – 3 V

Engine speed: 5,000 r/minSystem voltage
71Ignition switch-STEngine: Cranking8 V or more
72Intake air temperature
sensorIgnition switch: ONWhen intake air tempera-
ture is 0C3.2 – 3.8 V
When intake air tempera-
ture is 20C2.3 – 2.9 V
When intake air tempera-
ture is 40C1.5 – 2.1 V
When intake air tempera-
ture is 80C0.4 – 1.0 V
76Oxygen sensorEngine: Running at 2,000 r/min after having been
warmed up (Check using a digital type voltmeter)0 ↔ 0.8 V
(Changes repeatedly)
80Backup power supplyIgnition switch: OFFSystem voltage
81Sensor impressed
voltageIgnition switch: ON4.5 – 5.5 V
82Ignition switch-IGIgnition switch: ONSystem voltage
83Engine coolant
temperature sensorIgnition switch: ONWhen engine coolant
temperature is 0C3.2 – 3.8 V
When engine coolant
temperature is 20C2.3 – 2.9 V
When engine coolant
temperature is 40C1.3 – 1.9 V
When engine coolant
temperature is 80C0.3 – 0.9 V
84Throttle position sensorIgnition switch: ONSet throttle valve to idle
position0.3 – 1.0 V
Fully open throttle valve4.5 – 5.5 V
85Barometric pressure
sensor
Ignition switch: ONWhen altitude is 0 m3.7 – 4.3 V
sensor
When altitude is 1,200 m3.2 – 3.8 V
86Vehicle speed sensor
Ignition switch: ON

Move the vehicle slowly forward0 ↔ 5 V
(Changes repeatedly)

MANUAL TRANSMISSION OVERHAUL – Transmission22B-4
TRANSMISSION
DISASSEMBLY AND REASSEMBLY
1 2 34 5
6
78
910
11
18 Nm
69 Nm69 Nm 18 Nm
69 Nm
3.9 Nm32 Nm32 Nm
3
Disassembly steps
1. Transfer
J2. O-ring
3. Roll stopper bracket
4. Insulator washer
(EVOLUTION-IV only)
5. Shift cable bracketI6. Select lever
H7. Speedometer gear
8. Back-up lamp switch
9. Gasket
10. Plug
11. Gasket
NOTE:
For each service point, refer to Basic Manual. (Pub. No. S9806CNCP9)

REAR AXLE – Special Tools27-3
SPECIAL TOOLS
ToolNumberNameUse
MB991502MUT-II sub-
assemblyInspection of AYC
(diagnosis display by MUT-II)
MB991529Diagnosis code
check harnessInspection of AYC
(diagnosis display by AYC warning lamp)
MD998330
(MD998331)Oil pressure
gauge
(2,942 kPa)Hydraulic pressure measurement

MB991705Hose adapter
MB990925Bearing & oil seal
installer setPressfitting of oil seal
MB991115Oil seal installerPressfitting of oil seal
(used in combination with MB990938)
MD998812Installer capPressfitting of oil seal nism of vehicles with AYC>
MD998813Installer 100
MD998829Installer adapter
(60)

REAR AXLE – Special Tools / Troubleshooting 27-4
MB990925
Brass bar
Bar (one-touch type)Toolbox
Installer adapter
Tool number (MB990925)O.D. mmTool number (MB990925)O.D. mm
AMB99092639.0AMB99093363.5
MB99092745.0MB99093467.5
MB99092849.5MB99093571.5
MB99092951.0MB99093675.5
MB99093054.0MB99093779.0
MB99093157.0BMB990938–
MB99093261.0CMB990939–
TROUBLESHOOTING
BASIC TROUBLESHOOTING CONDITIONS
Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.
NOTE
Before starting the troubleshooting procedure, make sure that the following items have been checked
okay.

The correct steering wheel has been properly installed in the neutral position of the steering column
shaft.

Tire and wheel sizes are correct with correct specifications. Inflation pressure, balance, and wear
conditions are okay.

Wheel alignment is correct.

The engine, suspension, and other parts have not been remodeled so as to affect the AYC system.
DIAGNOSIS FUNCTION
READING THE DIAGNOSIS CODE
Read the diagnosis code using an MUT-II tester or the AYC warning lamp.
(Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.)
ERASING THE DIAGNOSIS CODE
Refer to Group 00 – How to Use Troubleshooting / Inspection Service Points.

REAR AXLE – Troubleshooting 27-5
3. INSPECTION CHART FOR DIAGNOSIS CODE
Diagnosis
code No.Diagnosis itemsRef. page
12Power supply voltage (valve power supply) system (open- or short-circuit)27-6
21FR wheel speed sensor system (open- or short-circuit)27-6
22FL wheel speed sensor system (open- or short-circuit)27-6
23RR wheel speed sensor system (open- or short-circuit)27-6
24RL wheel speed sensor system (open- or short-circuit)27-6
25Wrong-diameter tire27-8
26Faulty wheel speed sensor27-9
31Steer sensor (ST-1, ST-2, ST-N) system (open-circuit)27-10
32Steer sensor (ST-N) system (short-circuit)27-10
33Steer sensor (ST-N) system27-11
34Steer sensor (ST-1, ST-2) system (short-circuit)27-11
41TPS system (open- or short-circuit)27-12
51Longitudinal acceleration sensor system (open- or short-circuit)27-12
52Longitudinal acceleration sensor27-13
56Lateral acceleration sensor system (open- or short-circuit)27-12
61Stop lamp switch system (open-circuit)27-13
65ABS monitor system (open-circuit or defective ABS)27-14
71Proportioning valve system (open- or short-circuit)27-14
72Directional control valve (right) system (open- or short-circuit)27-15
73Directional control valve (left) system (open- or short-circuit)27-16
81AYC relay system (open- or short-circuit)27-17
82Electric pump system27-18
83Electric pump system27-19

REAR AXLE – Troubleshooting 27-8
Code No. 25: Wrong-diameter tireProbable cause
This code is output if the speed of any one of the four wheels exceeds a specified
level with respect to the average of the four wheel speed sensor outputs when the
steering wheel is in the straight-ahead position and the vehicle speed exceeds 20
km/h. At this time, the warning lamp does not light up.
Defective harness or connector

Defective AYC-ECU

Defective ABS-ECU

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)OKCheck the following connector:
B-95
YES
Is ABS diagnosis code No. 15 output?YESGroup 35* – Refer to Troubleshooting
Are correct tires mounted on all four
wheels?NO
Repair
NG
Repair

NO
Repair
NOCheck and repair the harness between
wheel 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 wheel speed sensor output volt-
age. (Refer to p. 27-37.)NGCheck wheel speed sensor and ABS
rotor. (Refer to Group 35B.)
YES
Check Wheel speed sensor for instal-
lation.NG
Repair
Are correct tires mounted on all four
wheels?
NG
Replace

REAR AXLE – Troubleshooting 27-9
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

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?YESRefer to Group 35B – Troubleshooting
NG
Repair

NG
Check and repair the harness between
wheel 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 wheel speed sensor output volt-
age. (Refer to P.27-37.)NGCheck wheel speed sensor and ABS
rotor. (Refer to Group 35B.)
Check wheel speed sensor for installa-
tion.NG
Repair
NG
Replace

REAR AXLE – Troubleshooting 27-13
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.27-42.)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