light MITSUBISHI 3000GT 1991 Service Manual

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lliSUPPLEMENTAL RESTRAINT SYSTEM (SRS)
- Troubleshootina 52B-23
L
MB991349SRS Check Harness
View ASRS Check Harness connector @
Diagnosis Fheck connector16R2166(5) Connect the now disconnected red harness-side SDU
connector
(l&pin) to the connector @ of the SRS Check
Harness.
(6) Check according to the flow chart below, using the
specified digital multi-meter.
III1 Body wiring harness dam-/1 Repair or replace the1Is there continuity between the No. 9terminal of SRS Check Harness connector@and the No. 8 terminal of the
diagnosis check connector (next to the
right side of the junction block)?
Diagnosis check connectorv
~ No
Is there continuity between the No. 13or No. 14 terminal of SRC Check
Harness connector @ and ground?
Yes
SDU is grounded.Repair or replace the body
+ wiring harness at the
location of the short cir-cuit.(Refer to P.52B-14.)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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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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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.
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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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529-28 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - TroubleshootingI
I NoIs the resistance between the No. 3 Is the resistance between the No. 3terminal of SRS Check Harness connec- terminal of SRS Check Harness connec-
tor @ and the No. 4 terminal normal? tor @ and the No. 4 terminal normal?Standard value: 2,000 k 400Standard value: 2,000 k 400
Yes
the terminals of the leftfront impact sensor normal?(Refer to P.526-26.)Standard value:2,000 k 40R
Yes
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Front wiring harness is
grounded or open.
IIJ
?No -Is the resistance between the No. 5) Is the resistance between-Noterminal of SRS Check Harness connec-tor @ and the No. 6 terminal normal?the terminals of the right
Standard value: 2,000 2 4Oflfront impact sensor normal?(Refer to P.52B-26.)Standard value:Yes2,000 t 40R
Yes
Front wiring harness is
grounded or open.
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CONTINUED ON NEXT PAGENOTE
- IMPORTANT
(1) After repairing the SRS, reconnect the battery cable, erase the diagnosis code memory from thedMulti-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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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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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.)
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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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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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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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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