1999 MITSUBISHI LANCER EVOLUTION VI light

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 27-20
5. INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection
procedure No.Ref. page
Communication between MUT-II and the whole system is not possible.127-20
Communicatio between MUT-II and AYC-ECU is not possible.227-21
AYC warning lamp does not light up when the ignition key is turned to “ON” (engine
stationary).327-22
AYC warning lamp remains lit up after the engine has started.427-23
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.527-23
Rear tires are noisy during low-speed cornering.
Vehicle skews.627-24
6. INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication between MUT-II and the whole system is
not possible.
Probable cause
The cause may be a malfunction of the power supply circuit or the ground circuit
of the diagnosis connector.
Defective diagnosis connector

Defective harness or connector
NG
Check and repair the harness between
power supply and diagnosis connector.
OK
Check the trouble symptom.
NG
Check and repair the harness between
body ground and diagnosis connector.
OK
Check the trouble symptom.
OK
Replace MUT-II.
Check the following connectors:
B-22, B-50NG
Repair
OK
Measure at B-22 diagnosis connector.

Disconnect the connector and
measure at the harness side.

Continuity across 4/5 and body
ground
OK:ConductingNG
Measure at B-22 diagnosis combina-
tion meter connector.

Voltage across 16 and body ground
OK:System voltageNGCheck the following connectors:
B-22, B-49, B-75, B-73NG
Repair

REAR AXLE – Troubleshooting 27-22
INSPECTION PROCEDURE 3
AYC warning lamp does not light up when the ignition key
is turned to “ON” (engine stationary).
Probable cause
The lamp power supply circuit is probably open-circuited, lamp bulb is out, or the
circuit between AYC warning lamp and AYC-ECU or AYC-ECU itself is defective.
Blown fuse

AYC warning lamp out

Defective harness or connector

Defective AYC-ECU
NG
Check and repair the harness between
ignition switch (IG
2) and AYC warning
lamp.
OK
Check the trouble symptom.
OK
Replace combination meter.
NG
Check the harness between AYC
warning lamp and AYC-ECU.NG
Repair
OK
Check the trouble symptom.OK
Replace AYC-ECU.
OK
Check the following connectors:
B-96, B-94, B-08NG
Repair
OK
Measure at B-96 AYC-ECU connector.

Disconnect the connector and
measure at the harness side.

Ignition switch: ON

Warning lamp when 36 is grounded
to body
OK:Lit upNGCheck the lamp bulb.NG
Replace
Measure at B-08 combination meter
connector.

Disconnect the connector and
measure at the harness side.

Ignition switch: ON

Voltage across 48 and body ground
OK:Symptom voltageNGCheck the following connectors:
B-08, B-74, B-76NG
Repair

REAR AXLE – On-vehicle Service 27-38
Waveform Observation Points
SymptomProbable causeAction
Waveform amplitude is too small, or no
waveform.Defective wheel speed sensorReplace sensor.
Waveform amplitude varies greatly. (No
problem ifthe smallest amplitude is 100
Excessive axle hub lateral and radial runoutReplace hub.
problem if the smallest amplitude is 100
mV or more)Poor AYC-ECU groundingRepair.
Noise on waveform or disturbed
waveform
Open-circuited sensorReplace sensor.
waveform
Open-circuited harnessRepair harness.
Improperly mounted wheel speed sensorCorrect sensor installation.
Missing or collapsed ABS rotor toothReplace 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

SRS – Air Bag Modules and Clock Spring52B-29
BCLOCK SPRING INSTALLATION
Align the mating marks of the clock spring and, after turning
the front wheels to the straight-ahead position, install the
clock spring to the column switch.
Mating Mark Alignment
Turn the clock spring clockwise fully, and then turn back it
approx. 3 4/5 turns counterclockwise to align the mating marks.
Caution
If the clock spring’s mating marks are not properly aligned,
the steering wheel may not be completely rotational during
a turn, or the flat cable within the clock spring may be
severed, obstructing normal operation of the SRS and
possibly leading to serious injury to the vehicle’s driver.
CSTEERING WHEEL INSTALLATION
1. Before installation the steering wheel, be sure to first
turn the vehicle’s front wheels to the straight-ahead
position and align the mating marks of the clock spring.
Caution
Be sure when installing the steering wheel, that the
harness of the clock spring does not become caught
or tangled.
2. After clamping, turn the steering wheel all the way in
both directions to confirm that steering is normal.
DPOST-INSTALLATION INSPECTION
1. Turn the steering wheel lightly to the left and right to
check if it can be operated properly without any
abnormality.
2. Reconnect the negative battery terminal.
3. Turn the ignition key to the “ON” position.
4. Does the “SRS” warning lamp illuminate for about 7
seconds, and then remain extinguished for at least 5
seconds after turning OFF?
5. If yes, SRS system is functioning properly.
If no, consult page 52B-6.
Mating marks
SRS warning lamp

SRS – Air Bag Module Disposal Procedures52B-36
Caution
1) Before deploying the air bag in this manner,
first check to be sure that there is no one
in or near the vehicle.
2) The inflator will be quite hot immediately
following the deployment, so wait at least 30
minutes to allow it to cool before attempting
to handle it. Although not poisonous, do not
inhale gas from air bag deployment. See
Deployed Air Bag Module Disposal
Procedures (P.52B-40) for post-deployment
handling instructions.
3) If the air bag module fails to deploy when the
procedures above are followed, do not go near
the module. Contact your local distributor.
(7) After deployment, dispose of the air bag module
according to the Deployed Air Bag Module Disposal
Procedures. (Refer to P.52B-40.)
DEPLOYMENT OUTSIDE THE VEHICLE
Caution
1. This should be carried out in a wide, flat area at least
6 m away from obstacles and other people.
2. Do not perform deployment outside, if a strong wind
is blowing, and if there is even a slight breeze, the
air bag module should be placed and deployed
downwind from the battery.
1. Disconnect the negative (–) and positive (+) battery cables
from the battery terminals, and then remove the battery
from the vehicle.
Caution
Wait at least 60 seconds after disconnecting the
battery cables before doing any further work. (Refer
to P.52B-4.).
2. Perform the following procedure to deploy each air bag
module.

(1) Remove the air bag module from the vehicle.
(Refer to P.52B-26.)
Caution
The connector of the driver’s side air bag module
is so constructed that the positive and negative
terminals are automatically short-circuited when
it is disconnected to prevent an accidental
deployment of the air bag resulting from static
electricity generation. Nevertheless, to eliminate
the slightest possibility of an accidental
deployment, always bear the following in mind;
the air bag module should be stored on a flat
surface and placed so that the pad cover face
up. Anything should not be placed on top of it.

SRS – Air Bag Module Disposal Procedures52B-39

(1) Remove the air bag module from the vehicle.
(Refer to P.52B-27.)
Caution
The connector of the front passenger’s side air
bag module is so constructed that the positive
and negative terminals are automatically
short-circuited when it is disconnected to prevent
an accidental deployment of the air bag resulting
from static electricity generation. Nevertheless,
to eliminate the slightest possibility of an
accidental deployment, always bear the following
in mind; the air bag module should be stored on
a flat surface and placed so that the pad cover
face up. Anything should not be placed on top
of it.
(2) Connect two wires, each six meters or longer, to the
two leads of SRS air bag adapter harness A and
cover the connections with insulation tape. The other
ends of the two wires should be connected to each
other (short-circuited), to prevent sudden unexpected
deployment of the air bag module.
(3) Connect the deployment wires to the SRS air bag
adaptor harness A, pass it beneath the tyre, and
wheel assembly, and connect it to the air bag module.
(4) Pass the thick wires into the hole of the air bag module
bracket, and secure it to the wheel of the old tyre
with wheel (4 locations), with the air bag facing
upwards.
Caution
1) Leave some space below the wheel for the
deployment wires.
If there is no space, the reaction of the air
bag deployment could result in damage of
the adaptor harness.
2) While deployment takes place, do not have
the connector of the SRS air bag adaptor
harness A inserted between the tyres.
SRS air bag
adapter
harness A
MB686560Connection
6 m or
longer
Two wires Insulation
tape
Deployment wire
Air bag module

CHASSIS ELECTRICAL – Headlamp54-32
HEADLAMP
SERVICE SPECIFICATIONS
ItemsStandard valueLimit
Headlamp
aiming
High
beam
Vertical direction25’ (22 mm) below horizontal line–
aiming
[Parenthe-
sized are
allowable
beam
Horizontal
directionLeft head-
lampParallel to direction of vehicle travel–
allowable
beam axis
deviations 3
m ahead of
Right head-
lamp15’ (13 mm) leftward from vertical line (V)–
m ahead of
headlamp.]Low
beam
Vertical direction25’ (22 mm) below horizontal line–p]beam
Horizontal directionPosition where 15* rising section intersects
vertical line (V)–
Headlamp intensity cd (Center of high-beam high intensity
zone)–15,000 or
more per
light
Cautions in Handling Headlamp Assembly
Each headlamp assembly has a plastic outer lens on. Observe the do’s and don’ts below when
handling the headlamps.

Do not leave the headlamps lit for longer than 3 minutes with a protective cover on.

Do not mask the outer lens surface by taping or in any other way.

Do not scrub the outer lens surface with a pointed tool.

Use the designated wax remover for cleaning the outer lens surface. Rinse it thoroughly.

Use the designated genuine bulbs.
SPECIAL TOOLS
ToolNumberNameUse
MB991502MUT-II sub as-
semblyETACS-ECU input signal checking