MITSUBISHI MONTERO 2000 Service Repair Manual

52B-1
SUPPLEMENTAL
RESTRAINT
SYSTEM (SRS)
CONTENTS
GENERAL INFORMATION 2..................
SRS SERVICE PRECAUTIONS 3..............
SPECIAL TOOLS 5..........................
TEST EQUIPMENT 6.........................
TROUBLESHOOTING 7.......................
SRS MAINTENANCE 19.....................
POST-COLLISION DIAGNOSIS 23............
INDIVIDUAL COMPONENT SERVICE 26......
WARNING/CAUTION LABELS 27.............FRONT IMPACT SENSORS 28...............
SRS AIR BAG CONTROL UNIT
(SRS-ECU) 30...............................
AIR BAG MODULES AND CLOCK
SPRING 32.................................
SIDE IMPACT SENSOR 41..................
AIR BAG MODULE DISPOSAL
PROCEDURES 43...........................
Undeployed Air Bag Module Disposal 43.........
Deployed Air Bag Module Disposal
Procedures 52.................................
CAUTION
DCarefully read and observe the information in the SERVICE PRECAUTIONS (P.52B-3.) prior to any service.
DFor information concerning troubleshooting or maintenance, always observe the procedures in the Troubleshooting
(P.52B-7.) section.
DIf any SRS components are removed or replaced in connection with any service procedures, be sure to follow the
procedures in the INDIVIDUAL COMPONENT SERVICE section (P.52B-26.) for the components involved.
DIf you have any questions about theSRS, please contact your local distributor.


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G
EN ER AL IN FO RM ATIO N
T o im pro ve sa fe ty , th e SR S are ava ila ble as optio nal
p arts . These syste m s enhance co llis io n sa fe ty by
r e str a in in g th e fr o nt passe ngers in ca se of an
a ccid ent.
T he SR S co nsis ts of fo ur air bag module s, SR S
a ir bag co ntr o l unit (S R S-E C U), fr o nt im pact
s e nso rs , sid e im pact se nso rs , SR S warn in g la m p
a nd clo ck sp rin g. The air bags are lo ca te d in th e
c e ntr e of th e ste erin g wheel, above th e glo ve box,
a nd built in to th e fr o nt se at back asse m blie s. E ach
a ir bag has a fo ld ed air bag and an in fla to r unit .
T he SR S-E C U under th e flo or co nso le monit o rs
t h e syste m and has a sa fin g G se nso r and an
a nalo g G se nso r. The fr o nt im pact se nso rs are
i n sta lle d on th e headla m p su pport panel. T he sid e
i m pact se nso r, w hic h is lo ca te d in sid e th e quarte r
p anels or ce nte r pilla r heelb ase > in ner, monit o rs any sh ocks co m in g
f r o m th e sid e of th e ve hic le . The warn in g la m p
o n th e in str u m ent panel in dic a te s th e opera tio nal
s ta tu s of th e SR S. The clo ck sp rin g is in sta lle d
i n th e ste erin g co lu m n.
T he SR S sid e air bag deplo ys if a n im pact re ce iv e d
a t th e sid e of th e ve hic le is str o nger th an ace rta in
s e t va lu e, in ord er to pro te ct th e upper bodie s of
f r o nt se at passe ngers in th e eve nt of a co llis io n.
O nly auth oriz e d se rv ic e pers o nnelsh ould do work
o n or aro und th e SR S co m ponents . T hose se rv ic e
p ers o nnelsh ould re ad th is m anualca re fu lly befo re
s ta rtin g any su ch work . E xtr e m eca re m ust b e use d
w hen se rv ic in g th e SR S to avo id in ju ry to th e se rv ic e
p ers o nnel (b y in adve rte nt deplo ym ent of th e air
b ags) or th e driv e r (b y re nderin g th e SR S
i n opera tiv e ). C
lo ck sp rin g D
riv e r’s air bag
m odule P
asse nger’s
a ir bag m odule
S R S-E C U D
ia gnosis
c o nnecto r
N O TE
* : In dic a te s th e parts equip ped on th e rig hta nd le ft sid es.
S
R S-E C U
S
id e air bag module
Sid e im pact se nso r* F
ro nt im pact se nso r
w
ww.W ork sh opM an uals .c o .u k
P urc h ased f r o m w ww.W ork sh opM an uals .c o .u k

S
R S SER VIC E PR EC AUTIO NS
1 . In ord er to avo id in ju ry to yo urs e lf or oth ers
f r o m accid enta ld eplo ym ento fth e air b ag durin g
s e rv ic in g, re ad and ca re fu lly fo llo w all th e
p re ca utio ns and pro ce dure s describ ed in th is
m anual.
2 . Do not use any ele ctr ic a l te st equip m ent on
o r near SR S co m ponents , exce pt th ose
s p ecif ie d on P.5 2B -6 .
3 .
Never Atte m pt to Rep air th e Follo w in g
C om ponen ts :
D S
R S air bag co ntr o l unit (S R S-E C U)
D F
ro nt im pact se nso r
D C
lo ck sp rin g
D D
riv e r’s and fr o nt passe nger’s air bag
m odule s
D S
id e air bag module
D S
id e im pact se nso r I
f any of th ese co m ponents are dia gnose d as
f a ult y , th ey sh ould only be re pla ce d, in
a cco rd ance wit h th e IN DIV ID UAL CO M -
P O NEN TS SER VIC E pro ce dure s in th is
m anual, sta rtin g at page 52B -2 6.
4 . Do nota tte m ptto re p air th e w ir in g harn ess co nnecto rs
o f th e SR S. If a defe ctiv e wir in g harn ess is fo und,
r e p air or re p la ce it by re fe rrin g to th e ta b le belo w .

D
estin atio n of harn ess R
em edy 1
,2 ,3 ,4 I
n str u m ent panel w ir in g harn ess ® Fro nt wir in g harn ess ® Fro nt
i m pact se nso r R
epair or re pla ce each wir in g
h arn ess. 7 I
n str u m ent panelw ir in g harn ess ® Earth R
epair or re pla ce th e in str u m ent 8 I
n str u m ent panelw ir in g harn ess ® SR S warn in g la m p p
anelw ir in g harn ess. 9
, 10 I
n str u m ent panelw ir in g harn ess ® Passe nger’s air bag module 1
1 , 12 I
n str u m ent panel w ir in g harn ess ® Clo ck sp rin g to driv e r’s air bag
m odule R
epla ce th e clo ck sp rin g orre pair
o r re pla ce th e in str u m ent panel
w ir in g harn ess. 1
3 I
n str u m ent panelw ir in g harn ess ® Ju nctio n blo ck (fu se No.8 ) R
epair or re pla ce th e in str u m ent 1
6 I
n str u m ent panelw ir in g harn ess ® Ju nctio n blo ck (fu se No.6 ) p
anelw ir in g harn ess. 2
0 I
n str u m ent panelw ir in g harn ess ® Dia gnosis co nnecto r 2
1,2 2 S
id e air bag wir in g harn ess ® Left sid e air bag module R
epair or re pla ce sid e air bag 2
3,2 4 S
id e air bag wir in g harn ess ® Sid e air bag module (R .H .) w
ir in g harn ess. 3
4, 35,
3 6 S
id e air bag wir in g harn ess ® Flo or w ir in g harn ess ® Sid e im pact
s e nso r (L .H .) R
epair or re pla ce each wir in g
h arn ess. 4
0, 41,
4 2 S
id e air bag wir in g harn ess ® Flo or w ir in g harn ess ® Sid e im pact
s e nso r (R .H .) B
atte ry B
atte ry ca ble (- )
w
ww.W ork sh opM an uals .c o .u k
P urc h ased f r o m w ww.W ork sh opM an uals .c o .u k

S
R S-E C U harn ess co nnecto r (re ar vie w ) M
B991222 S
R S-E C U harn ess co nnecto r M
B991222 N
o. N
am e A
pplic a tio n M
B991502 M
UT-II su b asse m -
b ly M
B991606 or
M B991613 S
R S ch eck har-
n ess C
heckin g SR S ele ctr ic a lcir c u it r y

H
arn ess se t
A : Check harn ess
B : LE D harn ess
C : LE D harn ess
a dapte r
D : Pro be C
heckin g co ntin uit y and measu rin g vo lt a ge at
S R S-E C U harn ess co nnecto r M
R372530 S
R S air bag adapt-
e r harn ess D
eplo yin g driv e r’s air bag module in sid e
v e hic le M
B686560 S
R S air bag adapt-
e r harn ess D
eplo yin g fr o nt passe nger’s air bag module
a nd sid e air bag module s in sid e or outs id e
v e hic le N
am e A
pplic a tio n D
ig it a lm ult i- m ete r C
heckin g SR S ele ctr ic a l cir c u it r y (U se mult i-
m ete r fo r w hic h th e m axim um te st cu rre ntis 2
m A or le ss at m in im um ra nge of re sis ta nce
m easu re m ent

T
R O UBLE SH O OTIN G
S TA NDARD FLO W OF DIA G NO STIC TR O UBLE SH O OTIN G
R efe r to GRO UP 00 -How to Use Tro uble sh ootin g/In sp ectio n Serv ic e Poin ts .
D IA G NO SIS FU NCTIO N
D IA G NO SIS CO DES CHEC K
C onnect th e MUT-
I I t
o th e dia gnosis co nnecto r (1 6-p in ) under th e in str u m ent co ve r, th en ch eck dia gnosis
c o des.
( R efe r to GRO UP 00 -How to Use Tro uble sh ootin g/In sp ectio n Serv ic e Poin ts .)
E R ASIN G DIA G NO SIS CO DES
W HEN USIN G TH E MUT-I
I
C onnect th e MUT-
I I t
o th e dia gnosis co nnecto r and era se th e dia gnosis co de.
C au tio n
T u rn off th e ig nit io n sw it c h befo re co nnectin g or dis co nnectin g th e MUT-I
I
.
S R S WARNIN G LA M P CHEC K
1 . Check th at th e SR S warn in g la m p co m es on when th e
i g nit io n sw it c h is tu rn ed ON.
2 . Check th at th e SR S warn in g la m p illu m in ate s fo r about
7 se co nds and th en goes out.
3 . If th is is not th e ca use , ch eck th e dia gnosis co des.
I N SPEC TIO N CHART FO R DIA G NO SIS CO DES
C ode No. D
ia gnosis it e m R
efe re nce
p age 1
1 , 12,1 3 F
ro nt im pact se nso r syste m 5
2B -8 1
4 F
ro nt im pact a nalo g G-s e nso r syste m in sid e SR S-E C U 5
2B -9 1
5,1 6 F
ro nt im pact sa fin g G-s e nso r syste m in sid e SR S-E C U 5
2B -9 1
7 S
id e im pact sa fin g G-s e nso r syste m in sid e SR S-E C U 5
2B -9 2
1*2
, 22*
2
, 61,6 2 D
riv e r’s air bag module (s q uib ) syste m 5
2B -1 0 2
4*2
,
2 5*
2
, 64,6 5 P
asse nger’s air bag module (s q uib ) syste m 5
2B -1 2 3
1,3 2 D
C-D C co nve rte r syste m in sid e SR S-E C U 5
2B -9 3
4*1 5
2B -1 3 3
5 S
R S-E C U (d eplo ye d air bag) syste m 5
2B -1 3 4
1*1 5
2B -1 3 4
2*1 5
2B -1 3

SRS -Troubleshooting52B-8
Code No.Reference
page Diagnosis item
43*1SRS warning lamp drive circuit systemLamp does not illuminate.52B-14
Lamp does not go out off.52B-14
44*1SRS warning lamp drive circuit system52B-14
45Internal circuit system of non-volatile memory (EEPROM) inside SRS-ECU52B-9
51, 52Driver’s air bag module (squib) system52B-9
54, 55Passenger’s air bag module (squib) system52B-9
71*2,72*2, 75, 76Side air bag module (R.H.) (squib) system52B-15
73, 74Side air bag module (R.H.) (squib) system52B-9
79, 93Side impact sensor (L.H.) communication system52B-16
81*2,82*2, 85, 86Side air bag module (L.H.) (squib) system52B-16
83, 84Side air bag module (L.H.) (squib ignition drive circuit) system52B-9
89, 96Side impact sensor (R.H.) communication system52B-17
91*1Side impact sensor (L.H.) power supply circuit system52B-17
92Analog G-sensor system inside side impact sensor52B-17
94*1Side impact sensor (R.H.) power supply circuit52B-18
95Analog G-sensor system inside side impact sensor (R.H.)52B-17
NOTE
1. *1: If the trouble(s) are extinguished, the SRS warning lamp will go out with diagnosis code history
automatically erased.
2. *2: If the vehicle condition return to normal, the diagnosis code will be automatically erased, and
the SRS warning lamp will return to normal.
3. If the vehicle has a discharged battery, it will store the fault codes 41 or 42. When these diagnosis
codes are displayed, check the battery.
INSPECTION PROCEDURE CLASSIFIED BY DIAGNOSIS CODE
Code No.11, 12 or 13 Front impact sensor systemProbable cause
These diagnosis codes are output if there is abnormal resistance between the
input terminals of the front impact sensors inside the SRS-ECU.
The trouble causes for each diagnosis code No. are as follow.DMalfunction of harness or connector
DMalfunction of front impact sensor
DMalfunction of SRS-ECU
Table 1
Code No.Trouble Symptom
11D
Short circuit in front impact sensor or harness
D
Short circuit in front impact sensor harness leading to the vehicle body ground
D
Short circuit in front impact sensor harness leading to the power supply
12D
Open circuit in either left or right front impact sensor or harness
D
Short circuit in front impact sensor harness leading to the power supply
13D
Open circuit in both left and right front impact sensor or harness
D
Short circuit in front impact sensor harness leading to the power supply


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SRS -Troubleshooting52B-9
OK
Check the trouble symptoms.
NG
Repair
OK
Replace the SRS-ECU.
Measure at SRS-ECU connector E-111.
DDisconnect the connector and measure at the harness
side.
DResistances between terminal 1 and 2, 3 and 4
NG:2
Wor less (short circuit)
NG:1M
Wor more (open circuit)
DContinuity between 1, 2, 3, 4 and body earth
OK: No continuityNGCheck the following connector:A-31, A-25, D-27, E-111
NG
Check the harness wire between the front impact sensor and
the SRS-ECU, and repair if necessary.
OK
Check the front impact sensor (Refer to P.52B-21.)
Code No.14, 15, 16, 17, 31, 32, 45, 51, 52, 54, 55, 73, 74, 83,
84 System inside SRS-ECUProbable cause
These diagnosis trouble codes are output when a fault is detected in the
SRS-ECU.
The trouble causes for each diagnosis code No. are as follows.Malfunction of SRS-ECU
Table 2
Code No.Defective partTrouble Symptom
14Front impact analog G-sensorD
When the analog G-sensor is not operating
D
When the characteristics of the analog G-sensor are
abnormal
D
When the output from the analog G-sensor is abnormal
15Front impact safing G-sensorShort circuit in the safing G-sensor
16Open circuit in the safing G-sensor
17Side impact safing G-sensorD
When the safing G-sensor is not operating
D
When the characteristics of the safing G-sensor are abnormal
D
When the output from the safing G-sensor is abnormal
31DC-DC converterVoltage at the DC-DC converter terminal is higher than the
specified value for five seconds or more.
32Voltage at the DC-DC converter terminal is lower than the
specified value for five seconds or more(this is not detected if
diagnosis code No.41 or 42 indicating battery voltage drop has
been output.)
45Non - volatile memory (EEPROM)When the non-volatile memory (EEPROM) is abnormal
51Driver’s side air bag moduleShort circuit in the squib ignition drive circuit
52(squib)Open circuit in the squib ignition drive circuit
54Passenger’s air bag moduleShort circuit in the squib ignition drive circuit
55(squib)Open circuit in the squib ignition drive circuit
73Side air bag module (R.H.) (squib)Short circuit in the squib ignition drive circuit
74Open circuit in the squib ignition drive circuit
83Side air bag module (L.H.) (squib)Short circuit in the squib ignition drive circuit
84Open circuit in the squib ignition drive circuit
Replace the SRS-ECU.


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SRS -Troubleshooting52B-10
Code No.21, 22, 61, 62 Driver’s side air bag module (squib)
systemProbable cause
These diagnosis codes are output if there is an abnormal resistance between the
input terminals of the driver’s side air bagmodule(squib) inside the SRS-ECU.
The trouble causes for each diagnosis code No. are as follow.
However, as for code Nos.21 and 22, if the vehicle’s condition return to normal,
SRS warning lampwill go out. (Diagnosis code will remain stored)DMalfunction of clock spring
DPartially open asclock spring is not in neutral
position
DMalfunction of harness or connector
DMalfunction of driver’s air bagmodule(squib)
DMalfunction of SRS-ECU
Table 3
Code No.Trouble Symptom
21D
Short circuit in driver’s air bag module (squib) or harness short
D
Short circuit in clock spring
D
Poor connector contact*
22D
Open circuit in driver’s air bag module (squib) or open harness
D
Open circuit in clock spring
D
Disconnected driver’s air bag module (squib) connector
D
Partially open as clock spring is not in neutral position
D
Poor connector contact
61Short circuit in driver’s air bag module (squib) harness leading to the power supply
62Short circuit in driver’s air bag module (squib) harness leading to the earth
NOTE
*: The shorting bars, which short positive (+) and negative ( - ) wires to prevent the air bags from accidental
deployment during the disconnection of the connector, are set in the squib circuit connectors. In
a defective connector, the short-bar may be still working even after the connection of the connecter.


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