1991 MITSUBISHI 3000GT clock

52B-24 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
TEST 4NO COMMUNICATION BETWEEN MULTI-USE TESTER AND SDU
(SRS warning light does not illuminate)
IGNITION SWITCH(IG1)
J/.8(MULTI -PURPOSEFUSES)
SRS DIAGNOSIS UNIT
MULTI -3SETESTER1
KKRS-AX-RISE+R
View ASRS diagnbsis unit
To front impact sensor
(L.H.)
\To front impact sensor (R.H.)Toclock spring
I19FOllO
To body wiring harness (14-pin)
onnectornotch -UNLOCKED
;;bb;;,LOCKED zRok
(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.
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i(4) Disconnect the red l4-pin connector from the SRS diagno- L/~
sis unit while pressing down the lock of the connector.
(Refer to
P.52B-9.)
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52B-26 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
TEST 5REPAIR REQUIRED FOR "11. G-SENS. TRBL I”, “12. G-SENS. TRBL 2” or
“13. G-SENS. TRBL 3” FAULT
SRS DIAGNOSIS UN1
IMPACT S!NSOR~M&N"E DETECTION
FRONT IMPACTSENS0RtL.H.)FRONT IMPACTsEN80R(R. H. )--u-~,w-*
Front impact sensor resistance checkDigital multi-meter
r ~1iii”~“‘.,,,,/ ?\I. I,// q
NOTEIf 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
Air bag module
(Squib)Short-circuitedOpen-circuitedShort-circuited
11 and/or 21
11 and/or 22One open-circuitedTwo open-circuited12 and/or 2113 and/or 21I12 and/or 2213 and/or 22
I
The numbers in the boxes are diagnosis codes numbers. (Refer to P.52B-20.)
/SRS diagnosis unit
View A
13u070rTo frontimDact sensor
(L.H.)
ITo clock springI19FOllO
To body wiring harness (14-pin)
lQFO102
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LSUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troub!eshooting 529-29
/ CONTINUED FROM PREVIOUS PAGE/*
(1)Connect the red 2-pin connector @ of the SRS CheckHarness to the SDU in place of the now-disconnected clock spring-SDU connector.
NOTEA 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)Reconnect blue.and yellow connectors, for the wiring
leading to the front impact sensors, to the SDU anddouble lock them. (Refer to
P.52B-9.)
NOTEIf double locking cannot be made, the connector isincorrectly or incompletely inserted; re-check to
insert the connector correctly and securely.
”
CONTINUED ON NEXT PAGEIMB991 349
SRS Check Harness
SRS CheckHarness
\ ii%\19FOO93NOTE
- IMPORTANT
(I) 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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id
cSUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troubleshooting 52B-31
1 CONTINUED FROM PREVIOUS PAGE(
(1) Remove the air bag module. (Refer to P.52B-62.)(2) Join the No. 2 and No. 7 connectors of the clock
spring to SRS Check Harness connector @ and SRSCheck Harness connector 0, respectively.
NOTEWhen joining SRS Check Harness connector 0, alignits white paint with the hollow portion of the No. 2
connector of the clock spring.
19FO109
MB991349
SRS Check Harness
No. 2 connector
of the clock spring
16R2190
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ICONTINUED ON NEXT PAGEI
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52B-32 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
CONTINUED FROM PREVIOUS PAGE
I/(1) Is the resistance between terminal 1 and terminal 21of SRS Check Harness connector @ and between
terminal 2 and terminal 22 of SRS Check HarnessMB991 349SRS Check Harnessconnector @ normal?
Standard value: less than 0.4R
No. 2 connector of clock springView A
To
co
of
SP
16R2190.
Yes
/
No
*
Malfunction of the clockspring.>V/
>Malfunction of the air bag
module.
CautionNever attempt to measure the circuit resistance of the air bag
module (squib) even if you are using the specified tester. If the
circuit resistance is measured with a tester, accidental air bagdeployment will result in serious personal injury.
NOTE
- IMPORTANT
(1) After repairing the SRS, reconnect the battery cable, erase the diagnosis code memory from the
Multi-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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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-36 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Troubleshooting
1 CONTINUED FROM PREVIOUS PAGE1(I) Remove the air bag module. (Refer to
P.52B-62.)(2) Join the No. 2 and No. 7 connectors of the clockspring to SRS Check Harness connector @ and SRSCheck Harness connector 0, respectively.
NOTEWhen joining SRS Check Harness connector 0, alignits white paint with the hollow portion of the No. 2
connector of the clock spring.
19FO109
MB991349
SRS Check Harness
No.2 connector
of the clock spring
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ICONTINUED ON NEXT PAGEI
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LSUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troubleshooting 52B-37
1 CONTINUED FROM PREVIOUS PAGE1(I) Is the resistance between terminal 1 and termir
ial 21of SRS Check Harness connector 0, and betweenterminal 2 and terminal 22 of SRS Check Harness
connector @ normal?
Standard value: less than 0.4fl
MB991 349
SRS Check HarnessNo. 2 connector of clock spring
View ASRS Check Harness connector@
Tocoof
sProfng
YesNo
Malfunction of the clock
spring.
+ ;z;;;tion of the air bag
> Replace the clock spring.
(Refer to P.52B-62.)
CautionNever attempt to measure the circuit resistance of the air bag
module (squib) even if you are using the specified tester. If the
circuit resistance is measured with a tester, accidental air bagdeployment will result in serious personal injury.
NOTE
- 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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