ignition MITSUBISHI 3000GT 1991 Service Manual

SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting 52B-25
r, NoIs there continuity between the No. 19‘1 ~~~~~i~k;~~~~.~~~-~4.~or No. 20 terminal of y:IsCheck ,-1 Ground circuit OpenIHarness connector @ and ground.
i
MB991349SW Check Harness
View ASRSCheckHarness Connector
use No. 1116R2186
Fusk No. 18
Gxnd(5) Connect the now disconnected red harness-side SDU
connector
(14-pin) to the connector @ of the SRS Check
Harness.(6) Check according to the flow chart below using the digital
multi-meter.
Reconnect negative terminal of
battery, and turn the ignitionkey to the “ON” position.
\I
I
Does the voltage between the No. 11terminal (of SRS Check Harness connec-tor 0) and the No. 19 or 20 terminal
(ground) indicate system voltage?
Does the voltage between the No. 12
terminal (of SRS Check Harness connec-tor 0) and the No. 19 or 20 terminal
(ground) indicate system voltage?
Yes
p Malfunction of the SDU+ (1) Turn the ignition key
to the “LOCK” po-
sition, disconnect
the negative battery
cable and tape theterminal.
(2) After waiting at least
30 seconds, replace
the SDU. (Refer to
P.52B-59.)NOTE
- IMPORTkNT
cd
(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)
?Du =-SRS Diagnosis Unit
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting 529-27
MB991 349
SRS Check HarnessFront impact
sensor con-
nectar (R.H.)@ (blue)
View ASRS Check Harness connector @
Left
Right
16R2189
(I) 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.
(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 lock lever.
Caution
A double-lock mechanism is employed for the connec-
tor of the SRS diagnosis unit, so care must be taken notto damage it by using excessive force or by not
disconnecting it correctly.(4) Disconnect each connector other than
14-pin connector
from the SRS diagnosis unit while pressing down the lock
of each connector. (Refer to
P.52B-9.)(5) Locate the blue and yellow connectors for the wiring
leading to the front impact sensors, which were connected
to the now-disconnected harness-side connector of the
SDU. Connect those blue and yellow connectors to
connector @ of the SRS Check Harness.
(6) Check according to the flow chart below, using the digital
multi-meter and Multi-use Tester.
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52B-30 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
1 CONTINUED FROM PREVIOUS PAGE-1
I/(I) Reconnect negative terminal of battery, and turn the.ignition key to the “ON” position.
(2) Using the Multi-use Tester, erase the diagnosis code_
memory. (Refer to TEST 1.)(3) Return the ignition key from the “ON” to the
“LOCK” position and then back to the “ON” position.
/
1 NoIs the SRS warning light operation
normal?) (1) Turn the ignition keyto the “LOCK” po-
Yessition, disconnect
the negative battery
cable and tape the
terminal.
(2) After waiting atleast 30 seconds,
replace the SDU.
(Refer to P.528-59.)
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) 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.
(3)Disconnect the red 2-pin connector of the SRS Check
Harness from the SDU while pressing down the lockof the connector. (Refer to
P.52B-9.)
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting 52B-33
1 TEST 6 )REPAIR REQUIRED FOR “21. SQUIB TRBL 1” or “22. SQUIB TRBL 2” FAULT1
i
FRONTSIDE
Ez
IGNITION SWITCH(IG1)CautionNever attempt to measure the circuit resistance of
the air bag module
(squib) even if you are using thespecified tester. If the circuit resistance is measuredwith a tester, accidental air bag deployment will
result in serious personal injury.
SRS DIAGNOSIS UNIT
------I
SELF-DIAGNOISISCHECK CONNECTOR(FOR MULTI-USETESTER)ms!+Ax-Pls95-Y
J/B
AIR (BSAgGU#DULEView A
SRS diagnosisunit
13uo704
To front impact sensor (L.H.1
\To front impact sensor (R.H.)
Todock springI19FOllOTo body wiring harness (IQpin)
No
Have the other diagnosis code test(s)/> Perform the other diagnosis
been finished?code test(s) prior to this test.
/I
Yes
NOTE
If combined front impact sensor and air bag module (squib) failure modes simultaneously
occur in two places, the preconditions for the respective detection circuits will go out of
order. For this reason, both diagnosis codes may not be stored but only one of them may
be indicated.Their relationships are shown in the following table.
Front impact sensors
Short-circuited One open-circuited Two open-circuited
Air bagShort-circuited11 and/or 2112 and/or 2113 and/or 21
module(Squib)Open-circuited11 and/or .2212 and/or 2213 and/or 22
The numbers in the boxes are diagnosis codes numbers. (Refer to P.52B-20.)
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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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1’SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troubleshooting 526-35
1 CONTINUED FROM PREVIOUS PAr/
J(I)
Reconnect negative terminal of battery, and turn the
(2)ignition key to the “ON” position.Using the Multi-use Tester, erase the diagnosis codememory. (Refer to TEST 1.)(3) Return the ignition key from the “ON” to the
“LOCK” position and then back to the “ON” position.
Is the SRS warning light operation)?IMalfunction-[
_Iv
’ (I) 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) 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 it by using excessive
force or by not disconnecting it correctly.
(3)Disconnect the red 2-pin connector of the SRS Check
Harness from the SDU while pressing down the lockof the connector. (Refer to
P.52B-9.)(I) Turn the ignition key
to the “LOCK” po-
sition, disconnect
the negative battery
cable and tape the
terminal.
(2) After waiting at least30 seconds, replace
the SDU. (Refer to
P.52B-59.)4
v MB991349
Resistor(302)19FOO93
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52B-38 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
TEST 7REPAIR REQUIRED FOR “33. CRANKING TRBL” FAULT1
STARTERHULAYIGNITIONSWITCH(ST>
7%INHIBITOR
10SWITCH
FI
pkEE&r -...__ -_-_-___I4SRS DIAGNOSIS UNITI
I---..-___________ - ____
2
14 13
!z
CLYL
da d4--__J/S
-A) @g
:6x36-NC-R1606-USRS diagnosis unit
13R0704View A
To front impact sensor (L.H.)
\To frontimpactsensor (R.H.)
II19FOllOTo clock spring
To body wiring harness (14-pin)
(I) 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.
(2) Remove the rear console assembly. (Refer to GROUP 52A-.
13R07211310722
- Floor Console.)
(3) Use a screwdriver to push in the lock spring of the lock
lever of the SRS diagnosis unit to unlock the lock lever.
Caution
A double-lock mechanism is employed for the connec-
tor of the SRS diagnosis unit, so care must be taken not
to damage the connector by using excessive force or bynot disconnecting it correctly.
(4) Remove the red
14-pin connector from the SRS diagnosis
unit while pressing down the lock of the connector. (Refer
to
P52B-9.1
I/’
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting 52B-39
MB991349SRS Check Harness
connector
View ASRS Check Harness connector @
Ground
II No(5) Connect the now disconnected red harness-side SDU
connector
(14-pin) to the connector @ of the SRS Check
Harness.(6) Check according to the flow chart below, using the digital
multi-meter.
IIIIs there continuity between the No. 191 or No. 20 terminal ofi;RSCheck‘1 ~~~~~;,0~~~~~~.~~~-14.~r1 Ground ‘jrcuit Open1Harness connector @ and ground?
Reconnect negative terminal of
(()
terminal (of SRS Check Harness connec-
tor 0) and the No. 19 or 20 terminal(ground) indicate system voltage?NOTE
- IMPOR
TANT
Yes
(1) Turn the ignition key
to the “LOCK” po-
sition, disconnect
the negative battery
cable and tape the
terminal.
(2) After waiting at least30 seconds, replacethe SDU.(Refer toP.52B-59.)
(1) Turn the ignition key
to the “LOCK” po-
sition, disconnect
the negative battery
cable and tape theterminal.
(2) After waiting at least
30 seconds, repair orreplace the body wir-ing harness. (Refer toP.52B-14.)
(1) If more than 45 seconds of cranking is required to start up the engine, the diagnosis code will be
stored in memory, but if there is no problem, the diagnosis code will be cleared and the SRS willreturn to normal.
(2) 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.)
(3) SDU
= SRS Diagnosis Unit
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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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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting 52B-41
1 TEST 9 1 REPAIR REQUIRED FOR “41. IG VOLT LOW 1” FAULT1
i
IGNITIONJTCH;
DIIll
MLLTI -PURPOSE
SRS DIAGNOSIS UNITr----------------------------A
f------ ‘iSRS diagnoiis unit
View A
To front impact sensor
(L.H.)
\To front impact sensor (R.H.)To
klock spring\19FOllO
To body wiring harness (14-pin)
+a-
Lock I
“(2 0-Ji9FO103-I-I
(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 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.(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 lock lever.
Caution
A double-lock mechanism is employed for the connec-
tor of the SRS diagnosis unit, so care must be taken notto damage it by using excessive force or by not
disconnecting it correctly.(4) Disconnect the red
14-pin connector from the SRS diagno-
sis unit while pressing down the lock of the connector.
(Refer to
P.52B-9.)