ECU MITSUBISHI 3000GT 1991 Service Manual

526-34 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
CONTINUED FROM PREVIOUS PAGE
c
(1) Turn the ignition key to the “LOCK” position,
disconnect the negative battery cable and tape the
terminal.
CautionWait at least 30 seconds after disconnecting the
battery cable before doing any further work. The
SRS system is designed to retain enough voltageto deploy the air bag for a short time even after
the battery has been disconnected, so serious
injury may result from unintended air bag deploy-ment if work is done on the SRS system im-
mediately after the battery cable is disconnected.(2) Remove the rear console assembly. (Refer to
GROUP 52A - Floor Console.)(3) Use a screwdriver to push in the lock spring of the
lock lever of the SRS diagnosis unit to unlock the locklever.
CautionA double-lock mechanism is employed for the
connector of the SRS diagnosis unit, so care mustbe taken not to damage it by using excessive
force or by not disconnecting it correctly.
(4) Disconnect the red
2-pin connector from the SDU
while pressing down the lock of the connector.
(Refer to
P.52B-9.)
/Lock spring
/Clock spring
I\(I) Connect the red connector @ of the SRS CheckHarness to the SDU instead of the now-disconnectedharness-side connector of the SDU, which were
connected to the air bag module (squib) through the
clock spring.
NOTE
SRS Check HarnessA
3-ohm resistor that corresponds to the resistance
of the air bag module (squib) and the wiring resis-
tance is connected between the terminals of the
connector
@ of the SRS Check Harness.
(2) Make the double locking.
NOTEIf double locking cannot be made, the connector is
incorrectly or incompletely inserted; re-check to
insert the connector correctly and securely.Connector @ ofSRS Check Harness
(3R)19 FOO9:
1
/
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52B-40 SUPPLEMENTAL ,RESTRAINT SYSTEM (SRS) - Troubleshooting
TEST 8REPAIR REQUIRED FOR “34. CONN. UNLOCKED” FAULT
SRS DIAGNOSIS UNIT-
r
--
L
FRONTSIDE
EESELF-DIAGNOSISCHECK CONNECTORLOCK SWITCH(FOR MULTI-USETESTER)KXB-AX-RIRW-YSRS diagnoskunit
13RQ7Q4View A
To front impact sensor
(L.H.)Todlock spring
I19F0110
To body wiring harness (14-pin)
(1) Turn the ignition key to the “LOCK” position,
disconnect the negative battery cable and tape
the terminal.
Caution
Wait at least 30 seconds after disconnectingthe battery cable before doing any further
work. The SRS system is designed to retainenough voltage to deploy the air bag for ashort time even after the battery has been
disconnected, so serious injury may result
from unintended air bag deployment if, work
is done on the SRS system immediately afterthe battery cable is disconnected.
(2) Remove the floor console. (Refer to GROUP
52A
- Floor Console.)
Is the SDU lock lever securely locked?~JII’~~
I11I
-1 Malfunction of the SDU> Replace the SDU.
(Refer to P.52B-59.1INOTE
- IMPORTANT
(1) After repairing the SRS, reconnect the battery cable, erase the diagnosis code memory from theMulti-use Tester and check the SRS warning light operation to verify the system functions
properly. (Refer to Test 1.)
(2) SDU
= SRS Diagnosis Unit
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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-611330721
13R072i
ht-----
SERVICE POINTS OF INSTALLATION
PRE-INSTALLATION INSPECTIONBefore SRS diagnosis unit is installed in the vehicle, it must be
visually inspected. If a dent, crack or other deformation is
detected, discard the SRS diagnosis unit and replace it with a
new one that passes the visual inspection.
6. INSTALLATION OF SRS DIAGNOSIS UNIT
With the projection part of the SRS diagnosis unit placed
against the bracket as shown in the figure, securely install
the SRS diagnosis unit.
CautionThe SRS may not activate properly if SRS diagnosis
unit is not installed properly, which could result in
serious injury or death to the vehicle’s driver.
5. CONNECTION OF THE SRS DIAGNOSIS UNIT AND
EACH HARNESS CONNECTORAfter connecting each harness connector securely and
correctly to the SRS diagnosis unit, be sure to press down
the lock lever of the SRS diagnosis unit.
POST INSTALLATION INSPECTION
Reconnect the negative battery terminal. Turn the ignition
switch to “ON”. Does the “SRS” 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.
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Air Bag Module
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - and Clock Spring52B-67Multi-use Testkr
ROM pack
(MB991 341)(MB991 359)
Diagnosis/
service
data
oumutGround
16LOO9'(3) Insert ROM pack into the Multi-use Tester and connect
tester to Diagnosis Check Connector in glove compart-
ment.
(4) Reconnect negative terminal of battery, and turn the
ignition key to the “ON” position.
(5) Conduct self-diagnosis using Multi-use Tester to ensure
entire SRS operates properly, except open circuit of air bag
module (“22. SQUIB TRBL 2”). (Refer to
P.52B-18.)(6) Turn 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.
11. INSTALLATION OF CLOCK SPRINGAlign the mating mark and “NEUTRAL” position indicator of
the clock spring, and, after turning the front wheels to the
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.
9. CLOCK SPRING AND SRS DIAGNOSIS UNIT CONNEC-
TIONAfter securely and correctly installing the clock spring’s
connector to the SRS diagnosis unit, be absolutely sure to
press down the lock lever of the SRS diagnosis unit.
13R072113R072;8. INSTALLATION OF STEERING WHEEL
(1) Before installing the steering wheel, be sure to first turn
the vehicle’s front wheels to the straight-ahead position
and align the mating mark and “NEUTRAL” position
indicator of the clock spring.
Caution
Be sure when installing the steering wheel, that the
harness of the clock spring does not become caughtor tangled.
(2) After clamping, turn the steering wheel all the way in
both directions to confirm that steering is normal.
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HEATERS AND MANUAL AIR CONDITIONER - Heater cmrol *=mW55-19
20A040fINSPECTION
BLOWER SWITCH
M55GCAIOperate the switch, and check the continuity between the
terminals.
NOTEo-0 indicates that there is continuity between the terminals.
SERVICE POINTS OF INSTALLATIONM55GDAQ
10. INSTALLATION OF TEMPERATURE CONTROL WIREConnect the temperature control wire to the blend air
damper lever by following the steps below.
(1) Move the temperature control lever to the rightmost
position. (“HOT” position)
(2) With the blend air damper lever pressed completely
downward in the direction indicated by the arrow,
connect the inner cable of the temperature control wireto the end of the blend air damper lever, and then
secure the outer cable by using a clip.
9.INSTALLATION OF MODE SELECTION CONTROL WIREConnect the mode selection control wire to the mode
selection damper lever by following the steps below.
(1) Move the mode selection lever to the
$$ position.
(2) With the mode selection damper lever pressed inwardin the direction indicated by the arrow, connect the
inner cable of the mode selection control wire to the
end of the mode selection lever, and then secure the
outer cable by using a clip.
3.INSTALLATION OF AIR SELECTION CONTROL WIREConnect the air selection control wire to the air selection
damper lever by following the steps below.
(1) Move the air selection control lever to the &ZI position.
(2) With the air selection damper lever pressed inward in
the direction indicated by the arrow, connect the inner
cable of the air selection control wire to the end of the
air selection lever, and then secure the outer cable by
using a clip.TSB Revision

55-24
IHEATERS AND MANUAL AIR CONDITIONER
- Blower Assembly
INSPECTIONM55KCAMl Check for bending or abnormal deflection of the rotating
Ishaft of the blower motor assembly.
l Check for cracking or deterioration of the packing.
l Check for damage to the fan.
d’l Check for damage to the blower case.
l Check the operation of the inside/outside air-selection
damper, and for damage.
16LO28C
BLOWER MOTOR ASSEMBLY CHECK(1) Disconnect the blower motor terminals.
(2) Connect the blower motor terminals directly to the batteryand check that the blower motor operates smoothly.
(3) Next, reverse the polarity and check that the blower motoroperates smoothly in the reverse direction.
SERVICE POINTS OF INSTALLATIONM55KDAH
10. INSTALLATION OF BLOWER MOTOR ASSEMBLY
Before installing the blower motor assembly, carefully clean
away any dust, dirt, etc. adhering to the inner surface of the
blower case.7. INSTALLATION OF AIR SELECTION CONTROL WIRE
Connect the air selection control wire to the air selection
damper lever by following the steps below.
(1) Move the air selection control lever to the CQ position.
(2) With the air selection damper lever pressed inward in
the direction indicated by the arrow, connect the inner
cable of the air selection control wire to the end of the
air selection lever, and then secure the outer cable byusing a clip.
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