1991 MITSUBISHI 3000GT Service Manual

i
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General Information526-7
:ONFIGURATION DIAGRAMS
q Engine compartmentA-09X
/
+m*,.16,IIfc’ \=is\ IL\\
\
\iw I \B/f---TJwdD
’ L&/Y&!!
3BFOO13
qEngine and transaxle (Front view)

B-23B-24Starter motor
B-26 Inhibitor switchA-38
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52B-8SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General Information
36FOOOlJ/C-57 Clock spring
C-59 Ignition switch
C-79 Self-diagnosis check
connector (For
Multi-use Tester)
IbJInstrument panel and floor console
D-
D-03
D-04Combination meter
D-05
D-2314-pin red connector
to body wiring harness
D-24Z-pin blue connector to
right front impact sensor
D-252-pin yellow connector to
left front impact sensor
D-262-pin red connector to
clock springConnector to
SRS Diagnosis
UnitD-26225
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General Information52B-9.ock sprinq
\ Secondary lock lever
13R0721Harness side
connectorPrimary lock
/(Improperly fitted state)SRS diagnosis
unit side connector
Forced down13RO664Secondarv
lock lever’
projection
(Properly fitted state)
Secondary
lock spring
u13RO685
Prll
13R068t
ITSB I
SRS CONNECTOR CONSTRUCTIONThe connector of the SRS diagnosis unit has a double lock
mechanism, fit verification mechanism and connector shorting
mechanism.
DOUBLE LOCK MECHANISMThe double lock mechanism comprises a mechanism for
locking the connector of the SRS diagnosis unit and the
connector of the harness, and a mechanism for locking the
locked connectors by the lock secondary lever mounted to the
SRS diagnosis unit side connector.
The secondary lock lever locking is done as the lock spring fits
in the notch of the connector.
The operating principle is described below.
When Connectors Are To Be Fitted
(I) The SRS diagnosis unit and harness side connectors are
fitted. (Primary lock)
(2) The secondary lock lever mounted to the SRS diagnosis
unit side connector is pressed down by finger until a click is
heard indicating that the connectors have been locked.
(Secondary lock)
If the harness and SRS diagnosis unit connectors do not
properly fit, the secondary lock lever side projection and the
harness side connector projection interfere with each other,
making it impossible to lock the connectors.
When Connectors Are Unlocked
(1) Press the lock spring on the lock lever side in with a flat tip
(--) screwdriver to unlock the secondary lock lever (secon-
dary lock).
Caution
Forced removal of the connector without releasing the
secondary lock lever will result in a damaged lock lever.(2) Press the primary lock of each of the harness side
connectors and remove the harness side connector.
FvisionI

52B-10SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General InformationI
FIT VERIFICATION MECHANISMSecondary
lock leverThe mechanism electrically verifies that the connectors of the
SRS diagnosis unit have been fitted. The operating principle is
:described below.
d
(
(1) Securely connect the SRS diagnosis un.it and harness side
connectors and press the secondary lock lever down to lock
the connectors.
sisiarness side connector
13R0687Short bar
nlnal13R068E
Press-fitted tab terminals
13R0689Short
terminal (open)
plate
IShort terminal
I13R06911(2) At the time, the short bar provided on the rear of the
secondary lock lever shorts the associated two pole
terminals of the SRS diagnosis unit. The SRS diagnosis unit
supplies monitoring current to the circuit to electrically
verify that the connectors have been locked.
CONNECTOR SHORTING MECHANISMThe mechanism is designed for prevention of accidental
explosion of the inflator when the clock spring connector (for
the squib circuit) is removed from the SRS diagnosis unit. The
operating principle is described below.
When Connectors Are Fitted
When the SRS diagnosis unit and clock spring connectors are
coupled, the circuit between the short terminals and clock
spring connector terminals are kept in the OFF state by the
partition plate provided in the connector of the SRS diagnosis
unit.
When Connectors &e DisconnectedWhen the clock spring connectors are disconnected from the
SRS diagnosis unit, the partition plate between the short
terminals and clock spring connector terminals is removed. As
a result, a short circuit is formed between the two poles of the
clock spring connector terminals to prevent generation of a
potential difference (current) between the squib terminals.
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General information52B-11
SRS CIRCUIT DIAGRAM
IGNITION SWITCH(IG1)
I
I2B-W
COMBINATION METER
(SRS WARNING LIGHT)M,/T ! A(T
1.4w x 2iE
1047
?I!
-y 105
pq!g$g@-: l2
&S&7._----~~-_-~~_-_------~~~----- --- -_-_____-
7 T
%mY
1
I
WITHOUTTHEFT-ALfiF!M
INHIBITORSSWITCH-I
WITHTIiFm-0
II18IIIIIIIIIfIIIIIIIIIIIII
II
1 .I
I
LT\
MICROCOMPUTER
M/T
?-w
m
6
A/T
mI>a
SELF-DIAGNOSIS
CHECK CONNECTOR
V;ETF;)T1-USE*
:X35-AX-RlSOQ-N.._
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52B-12SUPPLEMENTAL RESTRAINT SYSTEM (SRS) -General Information
CAUTION1.DO not repair, splice or modify SRS wiring (except for specific repairs to the body wiring harness shown on page QB-14
2.replace wiring if necessary, after reading and following all precautions and procedures in this manual.DO not use an analogue ohmmeter to check SRS wiring or components; use only special tools and digital multi-metershown on page 52B-16.
12B-W2B-W
,, 7
B-WI\.J/B0(MULTI-PURPOSEFUSES)
10A
0.85B-WI' 2
---_-__--_----_--------~---~~~--~~--~~-~-~----~---- --_5SRS DIAGNOSIS UNIT
= CONSTANT4I- -xI
> VOLTAGE CIRCUITCONDENSIDETECTIL,. vAI\vvII ,
vvvn ,n N~,11rrnm,vn
Ttttlr .,,,,,,a
l@i fTii51 l@!l %piJ’
/
-i----
EBI
102!x 101
‘o’ @ii?r
i 1I
z
dd
3) clEl $1BVIi2VI
Qy y2 qli y jl y2/
FRONTIMPACTFRONT ' - ' '
SENSOR
I!?--
IMPACT
SENSOR
(L.H.)OFF -If-(R. H. )II
CLOCKSPRING
(5QUIBjAIR QA$e_MODULE
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SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - General Information52B-13
COMPONENT LOCATION
I
i
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.52B-14 SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - SRS Service Precautions
SRS SERVICE PRECAUTIONSMBZPBAA
1.In order to avoid injury to yourself or others from3.accidental deployment of the air bag during SRSNever Attempt to Repair the Following Com-servicing, read and carefully follow all the
pre-
ponents:dcautions and procedures described in this
manu-l Front Impact Sensors
al.l SRS Diagnosis Unit (SDU)
2.Do not use any electrical test equipment on orl Clock Spring
near SRS components, except those specifiedl Air Bag Module
on
P.52B-16.If any of those components are diagnosed as
Never use an analogue ohmmeter.faulty, they should only be replaced, in accord-
ance with the INDIVIDUAL COMPONENT SER-
VICE procedures in this manual, starting at page
[52B-561.
4.Do not attempt to repair the wiring harness connectors of the
SRS. If any of the connectors is diagnosed
as fault, replace the wiring harness. If the wires are diagnosed as faulty, replace or repair the wiring
harness according to the following table.
SDUTerminalNo.
Harness
Connector
(No. ofTerminals,Color)
101
102
2pins,red
51
52
2pins,yellow
12pins,
blue
2
II
II
I2 IIi
I3 I
4
t---i
14 pins,
5red
16 t
LDestination of Harness
Clock springReplace clock
spring.
Bodywiring
*
HarnessFront wiring
* HarnessFront impact+ sensor (LH)
Replace withsensor cable.*
Front wiring
--) HarnessFront impact* Sensor (RH)
--
-+ Diagnosis check pinCorrect or replace
-+ Control wiring harness+ Ignition switch (ST). control wiring,
instrument panel
-+ General purpose fuse No. 11wiring harness
or body wiringharness.+ General purpose fuse No. 18
Instrument panel+ wiring harnessSRS warning* light
-I-
~ JunctionBpdYCorrect or replace
block-+ wrnng-+ Groundharnessbody wiring harness.
NOTE(I)
(2)The sensor cable marked with * is available as service part.
The sensor cable used as a replacement part is routed along the body wiring harness.
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