1999 MITSUBISHI LANCER EVOLUTION VI steering

STEERING – Power Steering Gear Box37A-17
INSPECTION
RACK CHECK

Check the rack tooth surfaces for damage or wear.

Check the oil seal contact surfaces for uneven wear.

Check the rack for bends.
PINION AND VALVE ASSEMBLY CHECK

Check the pinion gear tooth surfaces for damage or wear.

Check for worn or defective seal ring.
BEARING CHECK

Check for roughness or abnormal noise during bearing
operation.

Check the bearing for play.

Check the needle roller bearing for roller slip-off.
OTHER CHECK

Check the cylinder inner surface of the rack housing for
damage.

Check the boots for damage, cracking or deterioration.

Check the rack support for uneven wear or dents.

Check the rack bushing for uneven wear or damage.

SRS – General Information52B-2
GENERAL INFORMATION
To improve safety, the SRS is available as optional
part.
The SRS consists of two air bag modules, SRS
air bag control unit (SRS-ECU), SRS warning lamp
and clock spring. One air bag is located in the
centre of the steering wheel and another above
the glove box. Each air bag has a folded air bag
and an inflator unit. The control unit under the floor
console monitors the system and has a safing G
sensor and an analog G sensor. The warning lamp
on the instrument panel indicates the operationalstatus of the SRS. The clock spring is installed
in the steering column.
Only authorized service personnel should do work
on or around the SRS components. Those service
personnel should read this manual carefully before
staring any such work. Extreme care must be used
when servicing the SRS to avoid injury to the service
personnel (by inadvertent deployment of the air
bags) or the driver (by rendering the SRS
inoperative).
Air bag module
(Driver’s side)Clock springAir bag module
(Front passenger’s side)
Diagnosis
connector
SRS-ECU
SRS warning lamp

SRS – Special Tools / Test Equipment52B-5
SPECIAL TOOLS
ToolNumberNameUse
MB991502MUT-II sub
assembly
Reading diagnosis codes

Erasing diagnosis code

Reading trouble period

Reading erase times
MB991613SRS check
harnessChecking the SRS electrical circuitry
MB990803Steering wheel
pullerSteering wheel removal
MB686560SRS air bag
adapter harness A
Deployment of air bag modules and seat
belt with pre-tensioner inside the vehicle

Deployment of air bag module (front
passenger’s side) outside the vehicle
MR203491 or
MB628919SRS air bag
adapter harness BDeployment of air bag module (driver’s side)
outside the vehicle
TEST EQUIPMENT
ToolNameUse
Digital multi-meterChecking the SRS electrical circuitry
Use a multi-meter for which the
maximum test current is 2 mA or less
at the minimum range of resistance
measurement

SRS – SRS Maintenance52B-16
SRS COMPONENT VISUAL CHECK
Turn the ignition key to the LOCK (OFF) position, disconnect
the negative battery cable and tape the terminal.
Caution
Wait at least 60 seconds after disconnecting the battery
cable before doing any further work. (Refer to P.52B-3.)
SRS CONTROL UNIT (SRS-ECU)
1. Check SRS-ECU case and brackets for dents, cracks,
deformation or rust.
Caution
The SRS may not activate if the SRS-ECU is not
installed properly, which could result in serious injury
or death to the vehicle’s driver or front passenger.
2. Check connector for damage, and terminals for
deformation or rust.
Replace SRS-ECU if it fails visual check.
(Refer to P.52B-24.)
AIR BAG MODULES, STEERING WHEEL AND CLOCK
SPRING
1. Remove the air bag modules, steering wheel and clock
spring. (Refer to P.52B-25.)
Caution
The removed air bag modules should be stored in
a clean, dry place with the pad cover face up.
2. Check pad cover for dents, cracks or deformation.
Insulating tape
Battery
Battery (–) cable
SRS-ECU
Pad cover


Pad cover

SRS – SRS Maintenance52B-17
3. Check connector for damage, terminals deformities, and
harness for binds.
4. Check air bag inflator case for dents, cracks or deformities.
5. Check harness and connectors for damage, and terminals
for deformation.
6. Check clock spring connectors and protective tube for
damage, and terminals for deformation.
7. Visually check the clock spring case for damage.
8. Align the mating marks of the clock spring and, after
turning the vehicle’s front wheels to 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 mark is 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 or front passenger.
9. Install the steering column covers, steering wheel and
the air bag module.
10. Check steering wheel for noise, binds of difficult operation.
11. Check steering wheel for excessive free play.
REPLACE ANY VISUALLY INSPECTED PART IF IT
FAILS THAT INSPECTION. (Refer to P.52B-25.)
Caution
The SRS may not activate if any of the above
components is not installed properly, which could
result in serious injury or death to the vehicle’s driver
or front passenger.
Inflator case
Connector

Inflator case
Connector
Protective tube
Case
Mating marksProtective tube

SRS – Post-collision Diagnosis52B-20
REPAIR PROCEDURE
WHEN AIR BAG DEPLOYS IN A COLLISION.
1. Replace the following parts with new ones.

SRS-ECU (Refer to P.52B-24.)

Air bag module (Refer to P.52B-25.)
2. Check the following parts and replace if there are any
malfunctions.

Clock spring (Refer to P.52B-25.)

Steering wheel, steering column and intermediate
joint
(1) Check wiring harness (built into steering wheel)
and connectors for damage, and terminals for
deformation.
(2) Install air bag module to check fit or alignment
with steering wheel.
(3) Check steering wheel for noise, binds or difficult
operation and excessive free play.
3. Check harnesses for binding, connectors for damage,
poor connections, and terminals for deformation.
(Refer to P.52B-18.)
WHEN AIR BAG DOES NOT DEPLOY IN LOW-SPEED
COLLISION.
Check the SRS components. If the SRS components are
showing any visible damage such as dents, cracks, or
deformation, replace them with new ones. Concerning parts
removed for inspection, replacement with new parts and
cautionary points for working, refer to appropriate INDIVIDUAL
COMPONENT SERVICE, P.52B-22.

SRS – Post-collision Diagnosis52B-21
SRS-ECU
1. Check SRS-ECU case and brackets for dents, cracks
or deformation.
2. Check connector for damage, and terminals for
deformation.
Air bag modules
1. Check pad cover for dents, cracks or deformation.
2. Check connector for damage, terminals deformities, and
harness for binds.
3. Check air bag inflator case for dents, cracks or deformities.
4. Install air bag module to steering wheel to check fit or
alignment with the wheel.
Clock spring
1. Check clock spring connectors and protective tube for
damage, and terminals for deformation.
2. Visually check the case for damage.
SRS-ECU

Connector

Inflator case
ConnectorInflator case
Case Protective tube
Protective tube

SRS – Post-collision Diagnosis / Individual Component Service52B-22
Steering wheel, steering column and intermediate joint
1. Check wiring harness (built into steering wheel) and
connectors for damage, and terminals for deformation.
2. Install air bag module to check fit or alignment with steering
wheel.
3. Check steering wheel for noise, binds or difficult operation
and excessive free play.
Harness connector (body wiring harness)
Check harnesses for binding, connectors for damage, poor
connection, and terminals for deformation. (Refer to P.52B-18.)
INDIVIDUAL COMPONENT SERVICE
If the SRS components are to be removed or replaced as a result of maintenance, troubleshooting,
etc., follow each procedure (P.52B-24 – P.52B-31)
Caution
1. SRS components should not be subjected to hear over 93C, so remove the SRS-ECU, air
bag module and clock spring before drying or baking the vehicle after painting.
Recheck SRS system operability after re-installing them.
2. If the SRS components are removed for the purpose of check, sheet metal repair, painting,
etc., they should be stored in a clean, dry place until they are reinstalled.