1997 ACURA NSX sensor

Supplemental Restrain t Syste m (SRS )
Descriptio n
SRS Airba g Syste m
Th e SR S is a safet y devic e which , whe n use d i n conjunctio n wit h th e sea t belts , i s designe d t o protec t th e drive r an d pas -
senge r i n a fronta l impac t exceedin g a certai n se t limit .
Th e syste m is compose d o f lef t an d righ t das h sensors , th e SR S uni t (include s safin g sensor) , th e cabl e reel , driver' s
airbag , an d th e passenger' s airbag .
Sea t Bel t Tensioner s
Th e sea t bel t tensioner s ar e linke d wit h th e SR S airbag s t o furthe r increas e th e effectivenes s o f th e sea t belts . I n a front -
en d collision , th e tensioner s instantl y retrac t th e belt s firml y t o secur e th e occupant s i n thei r seats .
PASSENGER' S
AIRBA G
RIGH T DAS H SENSO R
SRS UNI T
PASSENGER' S SEA T BEL T
TENSIONE R
LEF T DAS H SENSO R
CABL E REE L DRIVER'
S
AIRBA G DRIVER'
S SEA T BEL T
TENSIONE R
Operation
A s show n i n th e diagra m below , th e lef t an d righ t das h sensor s ar e connecte d i n parallel . Th e paralle l se t o f sensor s i s
connecte d i n serie s t o eac h airba g inflato r circui t an d th e vehicl e battery . I n addition , a back-u p powe r circui t i s connecte d
i n paralle l wit h th e vehicl e battery . Th e back-u p powe r circui t an d th e safin g senso r ar e locate d insid e th e SR S unit .
Fo r th e SR S t o operate :
(1 ) On e o r bot h safin g senso r an d on e o r bot h das h sensor s mus t activate .
(2 ) Electrica l energ y mus t b e supplie d t o th e airba g inflato r b y th e battery , o r th e back-u p powe r circui t i f th e batter y
voltag e i s to o low .
(3 ) Airba g an d sea t bel t tensione r charge s mus t b e released . The n th e airbag s wil l deplo y an d th e tensioner s wil l
activate .
Self-diagnosi s syste m
A self-diagnosi s circui t i s buil t int o th e SR S unit ; whe n th e ignitio n switc h is turne d O N (II) , th e SR S indicato r ligh t come s o n
an d goe s of f afte r abou t si x second s i f th e syste m is operatin g normally . I f th e ligh t doe s no t com e on , o r doe s no t g o of f
afte r si x seconds , o r i f i t come s o n whil e driving , i t indicate s a n abnormalit y i n th e system . Th e syste m mus t b e inspecte d
an d repaire d a s soo n a s possible .
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Supplemental Restrain t Syste m (SRS )
Genera l Precaution s
Carefully inspec t an y SR S par t befor e yo u instal l it .
D o no t instal l an y par t tha t show s sing s of bein g
droppe d o r improperl y handled , suc h a s dents ,
crack s o r deformation :
— Airba g assembl y (driver' s an d passenger's) .
— Das h sensors .
— Cabl e reel .
— SR S unit .
— Sea t bel t tensione r (driver' s an d passenger's) .
Us e onl y a digita l multimete r t o chec k th e system . I f
it' s no t a Hond a multimeter , mak e sur e it s outpu t i s
1 0 m A (0.0 1 A ) o r les s whe n switche d t o th e smalles t
valu e i n th e ohmmete r range . A teste r wit h a highe r
outpu t coul d damag e th e airba g circui t o r caus e ac -
cidenta l deploymen t an d possibl e injury .
D o no t instal l use d SR S part s fro m anothe r car .
Whe n makin g SR S repairs , us e onl y ne w parts .
Excep t whe n performin g electrica l inspections , alway s
disconnec t bot h th e negativ e cabl e an d positiv e ca -
bl e a t th e batter y befor e beginnin g work .
Replacemen t o f th e combinatio n ligh t an d
wiper/washe r switche s an d cruis e contro l switc h
ca n b e don e withou t removin g th e steerin g wheel :
(se e sectio n 23 ) D
o no t tr y t o disassembl e th e airba g assembly . I f ha s n o
serviceabl e parts . Onc e a n airba g ha s bee n operate d
(deployed) , i t canno t b e repaire d o r reused .
Fo r temporar y storag e of the airba g assembl y durin g
service , pleas e observ e th e followin g precautions :
• Stor e th e remove d airba g assembl y wit h th e pa d sur -
fac e up .
If th e airba g is improperl y store d fac e
down , accidenta l deploymen t coul d prope l th e uni t
wit h enoug h forc e t o caus e seriou s injury .
SHORT CONNECTO R(RED)
Store th e remove d airba g assembl y o n a secur e fla t
surfac e awa y fro m an y hig h hea t sourc e (exceedin g
212°F/100°C ) an d fre e of an y oil , grease , detergen t
o r water .
CAUTION : Imprope r handlin g o r storag e ca n inter -
nall y damag e th e airba g assembly , makin g i t
inoperative .
If yo u suspec t th e airba g assembl y ha s bee n
damaged , instal l a ne w uni t an d refe r t o th e Deploy -
ment/Disposa l Procedure s fo r scrappin g o f th e
damage d airbag .
Airbag Handlin g an d Storag e
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Sensor Inspection

CAUTION: Take extra care when painting or doing

body work on any part of the dashboard lower panel.

Avoid direct exposure of the sensors or wiring to heat

guns, welding, or spraying equipment.

• Disconnect both the negative and positive battery

cables.

• Install the short connectors before working around

the dashboard lower panel or the SRS sensors.

• After any degree of frontal body damage, inspect

both dash sensors. Replace a sensor if it is dented,

cracked, or deformed.

• Be sure the sensors are installed securely.

BRACKET
DASHBOARD

LOWER PANEL

MOUNTING

BOLTS
Wiring Precautions

Never attempt to modify, splice or repair SRS wiring.

NOTE: SRS wiring can be identified by special

yellow outer protective covering.

• Be sure to install the harness wires so that they are

not pinched or interfering with other car parts.

• Make sure all SRS ground locations are clean and

grounds are securely fastened for optimum metal-

to-metal contact. Poor grounding can cause inter-

mittent problems that are difficult to diagnose.

DASH

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Supplemental Restrain t Syste m (SRS )
After a collisio n i n whic h th e airbag s wer e deployed , in -
spec t th e following :
1 . Inspec t th e das h sensor s fo r physica l damage . I f
th e sensor s ar e damaged , replac e them .
2 . Inspec t al l th e SR S wir e harnesses . Replace , don' t
repair , an y damage d harnesses .
3 . Inspec t th e cabl e ree l fo r hea t damage . I f ther e i s
an y damage , replac e th e cabl e reel .
4 . Remov e th e passenger' s lowe r dashboar d panel ,
th e glov e bo x lid , an d th e glov e box . Remov e th e
passenger' s airba g assembly , th e mountin g
bracket , an d fram e fro m th e dashboard . Remov e
th e suppor t bracke t fro m th e steerin g colum n
beam .
5 . Chec k fo r crack s aroun d th e passenger' s airba g
and glov e bo x openings . Us e a brigh t ligh t t o chec k
from below , an d a mirro r t o chec k fro m above . I f
an y crack s ar e found , replac e th e dashboard .
6 . Afte r th e ca r i s completel y repaired , tur n th e igni -
tion switc h on . I f th e SR S indicato r ligh t come s o n
fo r abou t si x second s an d the n goe s off , th e SR S
syste m is OK . I f th e indicato r ligh t doe s no t func -
tion properly , g o to SR S Troubleshooting .
Check fo r crack s
Inspectio n Afte r Deploymen t
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Troubleshooting
Self-diagnosis Functio n
The SR S uni t include s a self-diagnosi s function . I f ther e
i s a failur e in th e sensors , SR S unit , inflator , o r thei r cir -
cuits , th e SR S indicato r ligh t i n th e gaug e assembl y
goe s ON .
SRS INDICATO R LIGH T
As a syste m check , th e SR S indicato r ligh t als o come s
o n whe n th e ignitio n i s firs t turne d t o th e I I position . I f
th e ligh t goe s of f afte r approximatel y si x seconds , th e
syste m is OK .
I f th e SR S indicato r ligh t remain s o n (o r fail s t o com e o n
th e syste m chec k mode ) on e o f th e SR S component s
(o r th e wiring/connector s in-between ) i s faulty .
Troubleshootin g Precaution s
Always us e th e tes t harness . D o no t us e tes t
probe s directl y o n componen t connecto r ter -
minal s o r wires ; yo u ma y damag e the m o r th e
contro l unit .
Whe n connectin g an y o f th e tes t harnesse s t o
th e system , pus h th e connector s straight-in ; d o
no t ben d th e connecto r terminals .
Befor e disconnectin g th e airba g connector(s) ,
tur n of f th e ignitio n switc h an d wai t fo r a t leas t
thre e minute s t o le t th e capacito r i n th e back-u p
circui t discharge . Thi s wil l preven t a malfunctio n
o f th e sea t bel t tensioners .
Befor e disconnectin g an y par t o f th e SR S wir e
harness , instal l th e shor t connecto r (RED ) o n th e
airbag s an d bot h sea t bel t tensioners . Afte r in -
stallin g th e shor t connector s o n th e airbags ,
immediatel y instal l on e SR S Servic e Connecto r
(Too l Numbe r 07MAZ-SP0020A ) o n th e cabl e
ree l connecto r (fo r th e driver' s airbag) , an d
anothe r o n th e SR S mai n harnes s connecto r (fo r
th e passenger' s airbag) . Thi s wil l preven t an y
stati c electricit y fro m triggerin g th e sea t bel t
tensioner s befor e yo u disconnec t the m (se e pag e
24-10 ).
SR S Indicato r Ligh t Troubleshootin g
Possible conditions :
1. SR S indicato r ligh t doe s no t com e o n a t al l — se e
pag e 24-15 .
2 . SR S indicato r ligh t stay s o n constantl y — se e pag e
24-18 .
3 . SR S indicato r ligh t come s o n in combinatio n wit h a
failur e o f anothe r electrica l syste m (brak e syste m
light , malfunctio n indicato r lam p etc.) . Chec k fo r
damage/corrosio n a t th e under-das h fus e box .
NOTE :
Before startin g th e applicabl e troubleshooting ,
chec k th e conditio n o f al l SR S connector s an d
groun d points .
I f th e faul t i s no t foun d afte r completin g th e ap -
plicabl e troubleshooting , substitut e a known -
goo d SR S uni t an d chec k whethe r th e SR S in -
dicato r ligh t goe s off . I f i t does , th e origina l SR S
uni t mus t b e faulty ; replac e it .
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Dash Senso r Remova l
CAUTION :
D o no t damag e th e senso r wiring .
D o no t instal l use d SR S part s fro m anothe r car ,
Whe n repairin g a n SRS , us e onl y ne w parts .
Carefull y inspec t th e das h sensor s fo r sign s o f bein g
droppe d o r improperl y handled , suc h a s dents ,
crack s o r deformation .
1 . Disconnec t th e batter y negativ e cable , the n th e
positiv e cable .
2 . Befor e disconnectin g an y par t o f th e SR S wir e
harness , instal l th e shor t connector s (RED ) (se e pag e
24-10 ).
3 . Remov e th e dashboar d lowe r cover .
4. Pul l bac k th e carpeting , an d disconnec t th e 2 P con -
necto r betwee n th e das h senso r an d SR S mai n
harness .
DASH SENSO R (L )
SR S MAI N HARNES S2P CONNECTO R
5. Remov e th e tw o das h senso r mountin g bolt s fro m
th e senso r bracket , the n remov e th e das h sensor .
SENSOR BRACKE T
DASH SENSO RMOUNTIN G BOLT S
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Supplemental Restrain t Syste m (SRS )
Dash Senso r Installatio n
CAUTION:
B e sur e t o instal l the harnes s wire s s o tha t the y ar e
no t pinche d o r interferin g wit h othe r ca r parts .
Replac e a senso r i f i t i s dented , cracke d o r deformed .
Fo r th e SR S t o functio n properly , th e righ t an d lef t
sensor s mus t b e installe d o n th e prope r sides .
1 . B e sur e th e batter y cable s ar e disconnected .
2 . Instal l th e senso r securely .
SENSOR BRACKE T
DAS H SENSO R
MOUNTIN G BOLT S8 x 1.2 5 mm22 N- m (2. 2 kgf-m , 1 6 Ibf-ft )Replace .
3. Remov e th e shor t connector s (RED ) fro m th e pas -
senger' s airbag , an d remov e th e SR S Servic e
Connecto r fro m th e SR S mai n harness .
4 . Reconnec t th e passenger' s airba g 3 P connecto r t o
th e SR S mai n harnes s 3 P connector , the n reinstal l
th e glov e box .
5 . Remov e th e shor t connecto r (RED ) fro m th e driver' s
airbag , an d remov e th e SR S Servic e Connecto r
fro m th e cabl e reel . 6
. Reconnec t th e driver' s airba g 3 P connecto r t o th e
cabl e ree l connector . Attac h th e shor t connecto r
(RED ) t o th e acces s panel , the n reinstal l th e pane l
o n th e steerin g wheel .
7 . Remov e th e shor t connector s (RED ) fro m bot h sea t
bel t tensioners , the n attac h th e shor t connector s
(RED ) t o their holders .
8 . Reconnec t th e floo r wir e harnes s connector s t o th e
driver' s an d passenger' s sea t bel t tensioners .
9 . Reconnec t th e batter y positiv e cable , the n th e
negativ e cable .
10 . Afte r installin g th e das h sensor , confir m prope r sys -
te m operation :
Tur n th e ignitio n switc h O N (II) ; th e SR S indicato r
ligh t shoul d com e o n fo r abou t si x second s an d
the n g o off .
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