sensor ACURA NSX 1997 Service Repair Manual

Brake Switc h Tes t
1. I f on e o f th e brak e light s doe s no t g o on , chec k tha t
brak e ligh t bul b in th e tailligh t o r th e hig h moun t light .
2. I f non e o f th e brak e light s g o on , chec k th e No . 4 5
(2 0 A ) fus e i n th e under-hoo d fuse/rela y box .
3 . I f th e fus e an d bulb s ar e OK , disconnec t th e 4 P con -
necto r fro m th e brak e switch .
4P CONNECTO R
BRAKESWITtH
BRAK EPEDAL
4. Chec k fo r continuit y betwee n th e B an d C terminals .
Ther e shoul d b e continuit y wit h th e brak e peda l
pushed .
I f ther e i s n o continuity , replac e th e switc h o r ad -
jus t peda l heigh t (se e sectio n 19 ).
I f ther e i s continuity , bu t th e brak e light s d o no t
g o on , inspec t for :
— Poo r groun d (G401 , G402 , G403 , G551) .
— An ope n in th e WHT/GR N o r GRN/WH T wire .
— Fault y brak e ligh t failur e sensor s (se e pag e
23-155 ).
Hig h Moun t Brak e Ligh t Tes t
1. Ope n th e trun k li d an d engin e compartmen t lid .
2 . Disconnec t th e 2 P connecto r fro m th e trun k wir e
harness .
TRUNK WIR E HARNES S
SID E WIR E
HARNES S
View fro m termina l sid e Vie
w fro m
termina lside
3. Connec t a voltmete r positiv e lea d t o th e GRN/WH T
termina l an d th e negativ e lea d t o th e BL K termina l
o f th e sid e wir e harnes s sid e o f th e connector .
Pus h th e brak e pedal , an d chec k fo r voltag e betwee n
th e GRN/WH T an d th e BL K terminals . Ther e shoul d
b e batter y voltage .
I f ther e i s n o voltage , chec k for :
— Blow n No . 4 5 (2 0 A ) fus e i n th e under-hoo d
fuse/rela y box .
— A n ope n i n th e GRN/WH T o r BL K wire .
— Fault y brak e switch .
I f ther e i s batter y voltage , g o t o ste p 4 .
4 . Connec t batter y powe r t o th e GRN/WH T termina l
an d groun d t o th e BL K termina l o f th e trun k wir e
harnes s sid e o f th e connector .
Chec k tha t al l th e LED s o f th e hig h moun t brak e ligh t
go on .
If th e hig h moun t brak e ligh t doe s no t g o on ,
chec k fo r a n ope n i n th e wire s i n th e trun k lid .
I f th e wire s i n th e trun k li d ar e OK , replac e th e
hig h moun t brak e light .
I f som e o f th e LED s d o no t g o on , replac e th e hig h
moun t brak e ligh t assembly .
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Side Marker/Turn Signal/Hazard Flasher System

Description

To cope with dimensional requirements for the airbag components and to offer better operational feel, the turn signal

lever and the cancel mechanism are separated mechanically, and connected electrically instead.

The system cancels the turn signals electrically, by means of a solenoid, after a turn is made. A sensor mechanism which

consists of cancel cams on the steering shaft and a pair of switches, is used to monitor the steering shaft's position.

STEERING SHAFT

CANCEL CAM

CANCEL SWITCH

TURN SIGNAL LEVER

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Horns
Componen t Locatio n Inde x
SRS component s ar e locate d i n thi s area . Revie w th e
SR S componen t locations , precautions , an d procedure s
i n th e SR S sectio n 24 befor e performin g repair s o r ser -
vice .
UNDER-HOO D RELA YBOX A
HOR N SWITC HTest, pag e 23-25 1
Overhaul , sectio n 1 7
CABL
E REE L
Test , pag e 23-25 2
SECURITY HOR N
Test , pag e 23-25 0
UNDER-HOO DFUSE/RELAY BO X SECURIT
Y CONTRO LUNITInpu t Test , pag e 23-32 2
RIGHT HOR NTest, pag e 23-25 0 LEF
T HOR N
Test , pag e 23-25 0
Descriptio n
Security Alar m System :
Th e securit y alar m syste m is a n anti-thef t alar m system . I f someon e trie s t o ope n th e trunk , hoo d o r eithe r doo r withou t
th e ignitio n key , o r i f th e roo f i s no t full y latched , th e securit y contro l uni t sense s a signa l fro m th e sensor s an d activate s
relay s t o flas h th e headlight s an d soun d th e hor n fo r abou t tw o minutes .
HORN RELA Y
Wir e colors : ORN/BLK ,
WHT/GRN, L T GRN/WHT ,, WHT/GR N
Test, pag e 23-25 1
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Supplemental Restrain t Syste m (SRS )
Components/Wirin g Location s
CAUTION: Mak e sur e al l SR S groun d location s ar e clea n an d ground s ar e securel y attached .
NOTE:
• Al l SR S electrica l wirin g harnes s ar e covere d wit h yello w insulation .
• Replac e th e entir e affecte d SR S harnes s assembl y i f i t ha s a n ope n cirui t o r damage d wiring .
SRS INDICATO R LIGH T (I n th e gaug e assembly ) T O CRUIS E CONTRO L
Troubleshooting , pag e 24-1 3 SET/RESUME SWITC H
Gaug e assembly , Sectio n 23 . CABL E REE L t o
DRIVER' S AIRBA G
3P Connecto r
TO HOR N SWITC H
DRIVER' S AIRBA G ASSEMBL Y
(Airba g an d Inflator )
Removal/Installation ,page 24-34/24-3 5Disposal, pag e 24-3 7
CABL E REE L t oSR S MAI N HARNES S6P Connecto r
LEFT DAS H SENSO RRemoval/Installation ,page 24-47/24-4 8
CABLE REE LRemoval/Installation ,page 24-42/24-4 4
PASSENGER' S AIRBA G ASSEMBL Y
(Airba g an d inflator )
Removal/Installation ,
pag e 24-34/24-3 5
Disposal , pag e 24-3 7
SRS MAI N HARNES S toPASSENGER' S AIRBA G
3 P Connecto r
RIGH T DAS H SENSO R
Removal/Installation ,
page 24-47/24-4 8
SRS MAI N HARNES S
t o RIGH T DAS H SENSO R
2 P Connecto r
SRS MAI N HARNES SSRS MAI N HARNES S t o FLOO R WIR E HARNES S
4 P Connecto r
UNDER-DAS H
FUS E BO X
SR S MAI N HARNES S
to UNDER-DAS HFUSE BO X
2 P Connecto r
LEF T DAS H SENSO R
t o SR S MAI N HARNES S
2 P Connecto r
SRS UNI T(Includin g safin g sensor )Removal/Installation ,
pag e 24-49/24-5 2 PASSENGER'
S SEA T BEL T
TENSIONE R
Removal/Installation ,
pag e 24-51/24-5 2
Disposal , pag e 24-3 7
PASSENGER' S SEA T BEL T
TENSIONE R t o
FLOO R WIR E HARNES S
3 P Connecto r
FLOO R WIR E
HARNES S
DRIVER' S SEA T BEL T
TENSIONE R
Removal/Installation ,page 24-51/24-5 2Disposal, pag e 24-3 7
TEST HARNES SSOCKET16P Connecto r
SRS MAI NHARNES S SOCKE T
18 P Connecto r
SR
S MAI N HARNES S
t o FLOO R WIR E HARNES S
3 P Connecto r DRIVER'
S SEA T BEL T
TENSIONE R t o
FLOO R WIR E HARNES S
3 P Connecto r
FLOO
R WIR E
HARNES S
FLOOR WIR E HARNES S
t o INDICATO R LIGH T i n
GAUGE ASSEMBL Y
30P Connecto r
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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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