MITSUBISHI 3000GT 1991 Service Manual

SRS Maintenance and
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Post-coltision Diagnosis 52B-51
2-3 Air Bag Module, Steering Wheel and Clock Spring
Rtng gearRotor
Screw
3at ca
To remote controlswitchAir bag module
Remote control
switch (radio)
To body wiring harness
SRS diagnosisunit
19FO150
19FO119(1) Remove air bag module from steering wheel. (Refer to
P.52B-62.)
CautionWhen disconnecting the air bag module-clock spring
connector, take care not to apply excessive force to it.(2) Check pad cover for dents, cracks or deformities.
CautionThe removed air bag module should be stored in a
clean, dry place with the pad cover face up.
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52B-52 SUPPLEMENTAL RESTRAINT SYSTEM fSRSI - ~Z-%~~~~aK&%kTo air bagmodule
To SRS dragnosls unit
I19FOO89(3) Check hooks and connectors for damage, terminals defor-
mities, and harness for binds.
(4) Check air bag inflator case for dents, cracks or deformities.
\(5) Check harness (built into steering wheel) and connectors
~for damage, and terminals for deformities.LA
(6) Remove the steering wheel by using a steering wheel
puller.
CautionDo not hammer on the steering wheel. Doing so may
damage the collapsible column mechanism.
(7) Remove the steering column covers. (Refer to GROUP 52A
- Instrument Panel.)
(8) Remove the clock spring. (Refer to
P.52B-62.)
(9) Check clock spring connectors and protective tube for
damage, and terminals for deformities.
(10)Visually check the clock spring case and the gears for
damage.(1 l)Align the mating mark and “NEUTRAL” position indicator
and, after turning the vehicle’s front wheels to straight-
ahead position, install the clock spring to the column
switch.
CautionIf 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.
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SRS Maintenance and
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Post-collision Diagnosis 52B-53
2-4Front Wiring Harness and Body Wiring Harness
(12)lnstall the steering wheel, steering column covers and the
air bag module.
(13)Check steering wheel for noise, binds or difficult operation.
(14)Check steering wheel for excessive free play.
REPLACE ANY VISUALLY INSPECTED PART IF IT FAILS THAT
INSPECTION.(Refer to
P.52B-62.)
CautionThe SRS may not activate properly if any of the above
components is not installed properly, which could result inserious injury or death to the vehicle’s driver.
36FOO19(1) Check connectors for poor connections.
(2) Check harnesses for binds, connectors for damage, and
terminals for deformities.
REPLACE ANY CONNECTORS OR HARNESS THAT FAIL THE
VISUAL INSPECTION.
(Refer to
P.52B-14.)
CautionThe SRS may not activate properly if SRS harnesses or
connectors are damaged or improperly connected, whichcould result in serious injury or death to the vehicle’s
driver.
i
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52B-54 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - ZZ%K%~g~~~s
POST-COLLISION DIAGNOSISTEST EQUIPMENT TO BE USED FOR POST-COLLISION DIAGNOSIS
ToolNumberName
Use
MB991 341Multi-use tester subassemblyl Reading diagnosis codesl Reading trouble periodl Erasing diagnosis codel Reading erase times
MB991 359
ROM pack (for Multi-
use Tester
Multi-usejesterR'OM pack(MB991341)(MB991 359)
Diagnosis/
service data
output
I
16LOO9'Function Selection
Data ListTo inspect and service the SRS after a collision (whether or not
the air bag has deployed), perform the following steps.
1. SRS Diagnosis Unit Memory Check
(1) Insert ROM pack into the Multi-use Tester and connect
the tester to Diagnosis Check Connector in glove
compartment.
‘I i(2) Read (and write down) all displayed diagnosis codes.J’(Refer to
P.52B-18.)
NOTEIf the battery power supply has been disconnected or
disrupted by the collision, the Multi-use Tester cannot
communicate with the SRS diagnosis unit. Inspect and,
if necessary, repair the body wiring harness before
proceeding further.
(3) Select the “2. SERVICE DATA” function and read (and
write down) all displayed “91. TRBL PERIOD” (Fault
duration) and “92. ERASE TIMES” (how many times
memories are erased.). Refer to Multi-use Tester
Instruction Manual (MB991 342).
NOTEl Maximum stored period: 9999 minutes (approx-
imately 7 days)
l Maximum number of times to be stored: 250
(4) Erase the diagnosis codes and after waiting 45 seconds
‘dor more read (and write down) all displayed diagnosis
codes. (Refer to P.528-18.)
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - ~~~-~~~~~a~~g~~~s 52B-552. Repair Procedure
(1) If air bag deployed in the collision, remove the deployed
air bag module. (Refer to
P.52B-62.)(2) Check the SRS components using the table shown
below.
If the SRS components are showing any visible damage
such as dents, cracks, or deformation, replace them
with new ones.
Refer to appropriate INDIVIDUAL COMPONENT SER-
VICE, P.52B-56.
(3) Conduct self-diagnosis using Multi-use Tester to ensure
entire SRS operates properly except open circuit of air
bag module (22. SQUIB TRBL 2).
(4) Install new air bag module. (Refer to
P.52B-62.)
SRS ComponentsInspection(when air bag deploys in collision)Inspection (when air bag does not deploy
in low-speed collision)
Front impact sensors
Replace front impact sensors.(Refer to P.52B-56.)(1)Check front upper frame lower and sensor
brackets for deformities or rust.
(2)Check sensor cases for dents, cracks deformi-ties or rust.
(3)Check sensor harnesses for binds, connectors
for damage, and terminals for deformities.
SRS diagnosis unitSDU)Replace SRS diagnosis unit.(Refer to P.52B-59.)(1)Check SDU case and brackets for dents, cracksor deformities.(2)Check connectors and lock lever for damage,and terminals for deformities.
jir bag moduleReplace air bag module.(Refer to P.52B-62.)(1)Check pad cover for dents, cracks or deformi-ties.
(2)Remove air bag module from steering wheel.
Check hooks and connector for damage, termi-
nals for deformities, and harness for binds.
(Refer to P.52B-62.)(3)Check air bag inflator case for dents, cracks or
deformities.
(4)Install air bag module to steering wheel to.checlfit or alignment with the wheel.
Steering wheel/steering
(1)column/intermediateReplace steering wheel, steering
iointcolumn and intermediate joint.Remove air bag module from steering wheel.
(Refer to P.52B-62.)(Refer to GROUP 37A- Steering(2)Wheel and Shaft.)Check wiring harness (built into steering wheel)and connectors for damage, and terminals fordeformities.(3)Install air bag module to check fit or alignmentwith steering wheel.(4)Check steering wheel for noise, binds or
difficult operation and excessive free play,
Clock springReplace clock spring.(1)Check clock spring connectors and protective
tube for damage, and terminals for deformities.
(2)&/;yecheck the case and the gears for
Harness connectorIBody and Front wiring ’(1 )Check connectors for poor connections.
iarnessl(2)Check harnesses for binding, connectors for damage, and terminals for deformities.(Refer to P.52B-53 and P.52B-14.)
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52B-56SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - front lwtact sensors
INDIVIDUAL COMPONENT SERVICEIf the SRS components are to be removed or replaced as a result of maintenance, troubleshooting, etc.,
follow each procedure
(P.52B-56 - P.52B-68).L++(
Caution
1.SW components should not be subjected to heat over 93°C (2OO”F), so remove the front impactsensors, SRS diagnosis unit and 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.
FRONT IMPACT SENSORS
Caution1. Never repair or disassemble a front impact
sensor. If faulty, replace it.
2.Handle the front impact sensors very careful-
ly, taking care not to drop them or otherwise
subject them to impact. If a sensor is seen tobe dented, cracked, deformed or rusted,
replace it with a new one.
3.Replace sensors with new ones after the air
bag has deployed.
REMOVAL AND INSTALLATION
Removal steps
l *Post-installation inspectiona*1. Connection of the negative (-) battery
cable to the battery
2. Front splash shield extension
I)* 3. Front impact sensorI)*Pre-installation inspection
I19FO133
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Front impact Sensors52B-57Digital multi-meter
/
19FOlC
SERVICE POINTS OF REMOVAL1. DISCONNECTION OF THE NEGATIVE
(-) BATTERY
CABLE FROM THE BATTERYTurn the ignition key to the “LOCK” position, disconnect
the negative battery cable and tape the terminal.
Caution
Wait at least 30 seconds after disconnecting the battery
cable before doing any further work. The SRS system is
designed to retain enough voltage to deploy the air bagfor a short time even after the battery has been
disconnected, so serious injury may result from unin-
tended air bag deployment if work is done on the SRSsystem immediately after the battery cable is discon-
nected.
INSPECTION
(I) Check upper frame and sensor brackets for deformities or
rust.
(2) Check sensor harness for binds, connectors for damage,
and terminals for deformities.
(3) Check for dents, cracks or deformation of the front impact
sensor.
Caution
If a dent, crack, deformation or rust is detected, replacewith a
.new sensor.
(4) Remove the front impact sensor.
(5) Measure the resistance between terminals and check
whether it is within the standard value.
Standard value: 2,000 + 40
iZ
CautionAlways replace the sensor with a new one if the
resistance is not within the standard value.
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52B-58SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Front Impact Sensors
SERVICE POINT OF INSTALLATION
PRE-INSTALLATION INSPECTION
(1) Before any front impact sensor is installed in the vehicle, it
must be visually inspected. If a dent, crack or other
LAdeformation, or rust, is detected, discard the sensor and
replace it with a new one that passes the visual inspection.
(2) Before any front impact sensor is installed in the vehicle,
the resistance between its terminals must be confirmed to
be within the standard value.
Standard value: 2,000
-t 400
Use the digital multi meter. If the resistance is not within
that standard value range, discard it and replace it with a
new one that has the standard value.
19FOO6i4.
INSTALLATI’ON OF FRONT IMPACT SENSOR
(1) Bend the wiring harness slightly (to the extent that
there is no slack), and clip securely by using the clip of
the front impact sensor.
(2) Install the front impact sensor so that there is close
adherence of the upper surface of the front impact
sensor and the installation surface of the upper frame
d’(lower).
Caution
The SRS may not activate properly if a front impact
sensor is not installed properly, which could result
Iin serious injury or death to the vehicle’s driver.
POST-INSTALLATION INSPECTIONReconnect the negative battery terminal. Turn the ignition
switch to “ON”. Does the
“SW” warning light illuminate for
about 7 seconds, turn OFF and then remain extinguished for at
least 45 seconds? If yes, SRS system is functioning properly. If
no, consult page 52B-17.
19FOO72
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS)- SRS Diagnosis Unit (SDU) 52B-59
SRS DIAGNOSIS UNIT (SDU)M52PDBA
Caution1. Never attempt to disassemble or repair the
SRS diagnosis unit. If faulty, replace it.
2.Do not to drop or subject the SRS diagnosisunit to impact or vibration.
If denting, cracking, deformation, or rust are
discovered in the SRS diagnosis unit, replace
it with a new SRS diagnosis unit. Discard theold one.3. After deployment of an air bag, replace the
SRS diagnosis unit with a new one.
4.Never use an ohmmeter on or near the SRS
diagnosis unit, and use only the special testequipment described on
P.!i2B-16.
REMOVAL AND INSTALLATION
Removal steps
*aPost-installation inspectionaI)1. Connection of the negative
battery cable to the battery
2. Cup holder
19FO130
t-1
3. Console plug
4. Rear console assembly
a* l d5. Connection of the SRS diagnosis
unit and each harness connector
l *6. SRS diagnosis unit*cPre-installation inspection
2-pin yellow connector
to left front impact sensor
Z-pin red
tonneto clock sprrng
Z-pin dlueconnector
to right front
\Impact sensor14-pin red connector to body wlnng harness
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52B-60 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - SRS Diagnosis Unit (SW
0I/-Battery e
13R0721lSF1072:
SRS diagnosis unitView A13R0704
To front impact sensor
(L.H.)
\To front impact sensor (R.H.1\I
I- - -,I1
\To clock springTo body wiring harness (14-pin)19FOllt
r-TSB I
SERVICE POINTS OF REMOVAL1. DISCONNECTION OF THE NEGATIVE
(-) BATTERY
CABLE FROM THE BATTERYTurn the ignition key to the “LOCK” position, disconnect
the negative battery cable and tape the terminal.
Caution
Wait at least 30 seconds after disconnecting the battery
cable before doing any further work. The SRS system is
designed to retain enough voltage to deploy the air bagfor a short time even after the battery has been
disconnected, so serious injury may result from unin-
tended air bag deployment if work is done on the SRSsystem immediately after the battery cable is discon-
nected.5. DISCONNECTION OF THE SRS DIAGNOSIS UNIT AND
EACH HARNESS CONNECTOR(1) Use a screwdriver to push in the lock spring of the lock
lever of the SRS diagnosis unit to unlock the lock lever.
CautionA double-lock mechanism is employed for the
connector of the SRS diagnosis unit, so care mustbe taken not to damage the connector by using
excessive force or by not disconnecting it correctly.(2) Remove each connector from the SRS diagnosis unit
while pressing down the lock of each connector. (Refer
to
P.52B-9.)
INSPECTIONlCheck the SRS diagnosis unit case and brackets for dents,
cracks or deformities.
lCheck connectors and lock lever for damage, and terminals
for deformities.
CautionIf a dent, cracks, deformation or rust discovered,
replace the SRS diagnosis unit with a new one.
NOTEFor checking of the SRS diagnosis unit other than described
above, refer to the section concerning troubleshooting.
(Refer to
P.52B-17.)
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