ACURA RL KA9 1996 Service Repair Manual

DTC 4- 1 (Right-front) , 4- 2 (Left-front) , 4- 4 (Right-rear) , 4- 8 (Left-rear) :
Whee l Senso r
The AB S contro l uni t monitor s th e whee l senso r signa l durin g th e regula r diagnosi s (a t speed s o f 6 mp h (1 0 km/h ) o r
more) . Thi s diagnosi s i s no t performe d whe n th e parkin g brak e signa l i s ON . Th e AB S contro l uni t turn s th e AB S indicator
ligh t o n i f i t detect s tha t ther e i s n o whee l senso r signa l fro m th e wheel .
Possibl e causes :
Open circuit , interna l shor t o r shor t t o bod y groun d in th e whee l senso r
Ope n circui t o r shor t t o bod y groun d in th e positiv e (+ ) wir e betwee n th e whee l senso r an d AB S contro l uni t
Ope n circui t o r shor t t o bod y groun d i n th e negativ e (- ) wir e betwee n th e whee l senso r an d AB S contro l uni t
Positiv e (+ ) wir e shorte d t o th e negativ e (- ) wir e betwee n th e whee l senso r an d AB S contro l uni t
Loos e connecto r o r poo r contac t o f terminal s
Improper whee l senso r ai r ga p
Fault y AB S contro l uni t
Missin g o r damage d pulse r
Modulato r doe s no t decreas e pressur e properl y
Whee l loc k b y downshif t
Is th e resistanc e a s specified ?— Front : 700-1,10 0— Rear : 1,400-2,00 0
Chec k th e continuit y o f th e whee l
sensor :Check fo r continuit y betwee n th e
appropriat e whee l senso r 2 P con -
necto r termina l No . 2 an d bod y
ground .
Is ther e continuity ?
(To pag e 19-66 )
WHEE L SENSO R 2P CONNECTO R
DTC4-14- 24- 44-8
Appropriat e Whee l Senso rRight-fron tLeft-frontRight-rea rLeft-rear
Wire sid e o f femal e terminal s
Replac e th e appropriat e whee l
sensor .
Replac e th e appropriat e whee lsensor .
When vehicl e is driven , ABS
indicato r ligh t i s ON .
Wit h th e SC S servic e connec -
to r connecte d (se e pag e 19-40 ),
DTC s 4-1 , 4-2 , 4- 4 and/o r 4- 8
ar e indicated .
Chec k th e whee l senso r resis -
tance :
1 . Disconnec t th e appropriat e
whee l sensor * 2 P connector .
2 . Measur e th e resistanc e
betwee n th e No . 1 an d No . 2
terminals .
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Troubleshooting
DTC 4- 1 (Right-front) , 4- 2 (Left-front) , 4- 4 (Right-rear) , 4- 8 (Left-rear) :
Whee l Senso r (cont'd )
(From pag e 19-65 )
ABS CONTRO L UNI T 22 P CONNECTO R
Chec k fo r a shor t t o bod y groun d
i n th e whee l senso r positiv e (+ )
circuit :
1 . Disconnec t th e AB S contro l
uni t 22 P connector .
2 . Chec k fo r continuit y betwee n
th e appropriat e whee l senso r
positive (+ ) circui t terminal *and bod y ground . NOTE
: Chec k wit h th e appropriat e whee l
senso r 2 P connecto r disconnected .
DTC4-1 (Right-front )4-2 (Left-front )4-4 (Right-rear )4-8 (Left-rear )
Appropriat e Termina lNo. 5 : FR W (+ )No . 3 : FL W (+ )No . 15 : RRW(+ )No. 13 : RL W (+ )
Is ther e continuity ? Repai
r shor t t o bod y groun d in th e
positiv e (+ ) circui t wir e betwee n
th e AB S contro l uni t an d appropri -
at e whee l sensor . Wir
e sid e o f femal e terminal s
Chec k fo r a shor t t o bod y groun d
i n th e whee l senso r negativ e (- )
circuit :
Chec k fo r continuit y betwee n th e
appropriat e whee l senso r nega -
tiv e (- ) circui t terminal * an d bod y
ground .
DTC4-1 (Right-front )4-2 (Left-front )4-4 (Right-rear )4-8 (Left-rear )
Appropriat e Termina lNo. 4 : FR W (-)No . 2 : FL W (-)No . 16 : RR W (-)No . 14 : RL W (-)
Is ther e continuity ? Repai
r shor t t o bod y groun d in th e
negativ e (- ) circui t wir e betwee n
th e AB S contro l uni t an d appropri -
at e whee l sensor .
(T o pag e 19-67 )
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(From pag e 19-66 ) AB S CONTRO L UNI T 22 P CONNECTO R
FLW (+ ) (GRN/BLU )
Chec k th e whee l senso r resis -
tance:1. Connec t th e whee l senso r 2 Pconnector .2. Measur e th e resistanc e
betwee n th e AB S contro l uni t
22 P connecto r positiv e sid e
an d negativ e sid e terminal s o f
th e appropriat e whee l sensor* .
I s th e resistanc e a s specified ?
— Front : 700 - 1,10 0— Rear : 1,400-2,00 0 Chec
k fo r a n ope n i n th e whee l
senso r circuit :1. Connec t th e AB S contro l uni t22P connecto r appropriat epositive sid e terminal * t o bod ygroun d wit h a jumpe r wire .2. Disconnec t th e appropriat ewheel sensor * 2 P connector .3. Chec k fo r continuit y betwee ntermina l No . 2 an d bod yground . Wir
e sid e o f femal e terminal s
NOTE : Chec k wit h th e AB S contro l uni t 22 P
connecto r disconnected .
FL W (+ ) (GRN/BLU )FR
W (+ ) (GRN/BLK )
WHEE L SENSO R 2 P CONNECTO R
Termina l sid e o f
mal e terminal s
I s ther e continuity ? Repai
r ope n in th e positiv e (+ ) cir -
cui t wir e betwee n th e AB S con -
tro l uni t an d appropriat e whee l
sensor .
Repair ope n in th e negativ e (- ) cir -
cui t wir e betwee n th e AB S con -
tro l uni t an d appropriat e whee l
sensor .
Correc t th e appropriat e whee lsensor ai r gap .
Measur e th e appropriat e whee l
senso r ai r ga p (se e pag e 19-103) .
Is th e ai r ga p OK ?
Chec k th e AB S functio n (se e pag e19-95 ).
JUMPE R WIR E JUMPE
R WIR E
Appropriat e Termina lPositive Sid e Negativ e Sid e4-1 (Right-front ) No . 5 : FR W (+ ) No . 4 : FR W (-)4- 2 (Left-front ) No . 3 : FL W (+ ) No . 2 : FL W (-)4- 4 (Right-rear ) No . 15 : RR W (+ ) No . 16 : RR W (-)4- 8 (Left-rear ) No.13 : RL W (+ ) No . 14 : RL W (-)
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Troubleshooting
DTC 5 , 5-4 , 5-8 : Rea r Whee l Loc k
The AB S contro l uni t monitor s th e rea r whee l senso r signal s durin g th e regula r diagnosi s (durin g driving) . Thi s diagnosi s
is no t performe d whe n th e parkin g brak e signa l i s ON . Th e AB S contro l uni t turn s th e AB S indicato r ligh t o n if i t detect s n o
signal(s ) fro m th e rea r whee l sensor(s ) du e to , fo r example , rea r whee l lock .
Possibl e causes :
Wheel spi n durin g cornerin g
Open circuit , interna l shor t o r shor t t o th e bod y groun d in th e whee l senso r syste m
Rear brak e dra g
Modulato r doe s no t decreas e pressur e properl y
Faulty AB S contro l uni t
— Whe n vehicl e i s driven , ABSindicato r ligh t i s ON .— Wit h th e SC S servic e connec -tor connecte d (se e pag e 19-40 ),DTC s 5 , 5- 4 and/o r 5- 8 ar e indi -
cated .
Chec k th e PAR K circuit :
1. Tur n th e ignitio n switc h O N (II) .2. Pres s th e parking brake pedal .
Doe s th e brak e syste m ligh t
com e on ? Parkin
g brak e switc h stuc k OFF .
Repai r ope n circui t betwee n th e
under-das h fuse/rela y bo x an d
parkin g brak e switch .
NOTE:The self-diagnosi s o f th e whee l senso r i s per -forme d i n thi s step .
Test-driv e wit h th e parkin g brak e released .
Does th e AB S indicato r ligh tcom e on ?
Chec k fo r rea r brak e drag :
1 . Rais e th e rea r o f th e vehicle ,
and suppor t i t wit h safet ystands (se e sectio n 1 ).2 . Spi n th e lef t and/o r righ t rea rwhee l an d chec k fo r brak e
drag . I
s cod e 4- 4 o r 4- 8 indicated ?
Perform th e troubleshootin g fo rthe rea r whee l sensor .
Perfor m th e appropriat e trouble -
shootin g fo r th e code .
Doe s th e brak e drag ?
Repair th e rea r brak e drag .
Check th e AB S functio n (se epage 19-95 ).
Th e probabl e caus e wa s tha t
tractio n wa s los t du e t o exces -
siv e cornerin g speed , etc .
Chec
k th e self-diagnosis :
Test-driv e th e vehicl e a t speed s
of 6 mp h (1 0 km/h ) o r more .
Confir m th e DT C (se e pag e 19-40 ).
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DTC 6 : Fron t an d Rea r Fail-saf e Relay s
The AB S contro l uni t monitor s th e voltag e fro m th e batter y fo r th e si x solenoid s durin g th e initia l diagnosi s whe n th e fail -
safe relay s ar e OFF . Th e AB S contro l uni t keep s th e AB S indicato r ligh t o n if i t detect s batter y voltag e a t th e fron t an d rea r
solenoi d circuits .
Possible causes :
Short t o powe r i n th e rela y driv e circuit s betwee n th e fail-saf e relay s an d AB S contro l uni t
Fault y rela y driv e transisto r (ON ) i n th e AB S contro l uni t
Doe s th e AB S indicato r ligh t g ooff ?
Th e AB S is O K a t thi s time . Chec k
fo r damage d wir e harnes s
betwee n th e AB S contro l unit ,
solenoid s an d fail-saf e relay s (inter -
mitten t shor t t o power) .
I s cod e 6 indicated ? Perfor
m th e appropriat e trouble -
shootin g fo r th e code .
(T o pag e 19-70 )
Wit
h engin e running , AB S indi -
cato r ligh t i s ON .
Wit h th e SC S servic e connec -
to r connecte d (se e pag e 19-40 ),
DT C 6 is indicated .
Proble m verification :
Star t th e engine .
Confir m th e DT C tha t appear s first .
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Troubleshooting
DTC 6 : Fron t an d Rea r Fail-saf e Relay s (cont'd )
(From pag e 19-69 )
Chec k fo r a shor t t o powe r i n th e
FS R circuit :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e AB S contro lunit 22 P connector .3. Star t th e engine .
4 . Measur e th e voltag e betwee n
termina l No. 1 an d bod yground .
ABS CONTRO L UNI T 22 P CONNECTO R
I s ther e batter y voltage ? Repai
r shor t t o powe r i n th e wir e
betwee n th e ABS contro l unit ,and fron t an d rea r fail-saf e relays .
I s ther e batter y voltage ? Replac
e th e AB S contro l unit .
(Fault y fail-saf e rela y driv e tran -
sistor )
Perfor m th e troubleshootin g fo r
DT C 6- 1 (se e pag e 19-71 ) an d
DT C 6- 4 (se e pag e 19-74 ). Wir
e sid e o f femal e terminal s
Chec k th e AB S contro l unit :
1. Tur n th e ignitio n switc h OFF .2. Connec t th e AB S contro l uni t22P connector .3. Tur n th e ignitio n switc h O N (II) .4. Measur e th e voltag e betwee ntermina l No. 1 an d bod yground .
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DTC 6-1 : Fron t Fail-saf e Rela y
The AB S contro l uni t monitor s th e voltag e fro m th e batter y fo r th e si x solenoid s durin g th e initia l diagnosi s whe n th e fail -
safe relay s ar e OFF . Th e AB S contro l uni t keep s th e AB S indicator light o n if i t detect s batter y voltag e a t th e fron t solenoi d
circuits.
Possible causes :
Front fail-saf e rela y stuc k O N
Shor t t o powe r i n th e solenoi d driv e circuit s betwee n th e fron t fail-saf e rela y an d AB S contro l uni t
Doe s th e AB S indicato r ligh t g ooff ?
Is cod e 6- 1 indicated ?
YES
Chec k th e fron t fail-saf e rela y (se e
sectio n 23 ).
I s th e rela y OK ?
Chec k th e modulato r wir e har -
ness :1. Disconnec t th e modulato r uni t14P connector .2. Visuall y chec k th e modulato rwire harness .
Is ther e a shor t t o power ?
(T o pag e 19-72 ) Th
e AB S is O K a t thi s time . Chec k
fo r damage d wir e harnes s betwee n
th e AB S contro l unit , solenoid s an d
fail-saf e relay s (intermitten t shor t
t o power) .
Perfor m th e appropriat e trouble -
shootin g fo r th e code .
Replac e th e fron t fail-saf e relay .
Replac e th e modulato r wir e har -
nes s (o r repai r short) .
Confir
m th e DT C tha t appear s first .
Proble
m verification :
Start th e engine .
With engin e running , AB S indi -
cato r ligh t i s ON .
Wit h th e SC S servic e connec -
to r connecte d (se e pag e
19-40 ), DT C 6- 1 i s indicated .
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Troubleshooting
DTC 6-1 : Fron t Fail-saf e Rela y (cont'd )
(From pag e 19-71 )
Chec k fo r a shor t t o powe r i n th e
SOLENOI D circuit :
1. Star t th e engine .2. Measur e th e voltag e betwee n
th e fron t fail-saf e rela y connec -
to r No . 1 termina l an d bod y
ground .
I s ther e batter y voltage ?
Chec k fo r a shor t t o powe r i n th e
FR-I N circuit :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e AB S contro l uni t
26 P connector .
3 . Star t th e engine .
4 . Measur e th e voltag e betwee n
termina l No . 2 an d bod y ground .
I s ther e batter y voltage ?
Chec k fo r a shor t t o powe r i n th e
FL-I N circuit :
Measur e th e voltag e betwee n th e
AB S contro l uni t 26 P connecto r
termina l No . 1 an d bod y ground .
I s ther e batter y voltage ?
(T o pag e 19-73 )
FRON T FAIL-SAF E RELA Y CONNECTO R
NOTE: Th e fail-saf e relay s ar e OF F whe n th e
AB S indicato r ligh t i s kep t on .SOLENOI D(BRN/BLK )
Repair shor t t o powe r i n th e wir e
betwee n th e fron t fail-saf e rela y
and modulato r unit .
Termina l sid e o f femal e terminal s
NOTE : Chec k wit h th e modulato r uni t U P
connecto r disconnected . AB
S CONTRO L UNI T 26 P CONNECTO R
Repai r shor t t o powe r i n th e wir e
betwee n th e AB S contro l uni t
an d modulato r unit .
Wire sid e o f femal e terminal s
Repair shor t t o powe r i n th e wir e
betwee n th e AB S contro l uni t
an d modulato r unit .
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(From pag e 19-72 )
Chec k fo r a shor t t o powe r i n th e
FR-OU T circuit :
Measur e th e voltag e betwee n th eAB S contro l uni t 26 P connecto r
termina l No . 1 5 an d bod y ground .
I s ther e batter y voltage ?
Chec k fo r a shor t t o powe r i n th e
FR-OU T circuit :
Measur e th e voltag e betwee n th e
AB S contro l uni t 26 P connecto r
termina l No . 1 4 an d bod y ground .
I s ther e batter y voltage ? Repai
r shor t t o powe r i n th e wir e
betwee n th e AB S contro l uni t
an d modulato r unit . AB
S CONTRO L UNI T 26 P CONNECTO R
Wir e sid e o f femal e terminal s
Repai r shor t t o powe r i n th e wir e
betwee n th e AB S contro l uni t
an d modulato r unit .
Chec k fo r loos e AB S contro l uni t
connectors . I f necessary , substi -
tut e a known-goo d AB S contro l
uni t an d recheck .
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Troubleshooting
DTC 6-4 : Rea r Fail-saf e Rela y
The AB S contro l uni t monitor s th e voltag e fro m th e batter y fo r th e si x solenoid s during the initia l diagnosi s whe n th e fail -
safe relay s ar e OFF . Th e AB S contro l uni t keep s th e AB S indicato r ligh t o n i f i t detect s th e batter y voltag e a t th e tw o rea r
solenoi d circuits .
Possible causes :
Rear fail-saf e rela y stuc k O N
Shor t t o powe r i n th e solenoi d driv e circuit s betwee n th e rea r fail-saf e rela y an d AB S contro l uni t
Doe s th e AB S indicato r ligh t g ooff ?
Th e AB S is O K a t thi s time . Chec k
fo r damage d wir e harnes s bet -
wee n th e AB S contro l unit , sole -
noi d an d rea r fail-saf e rela y
(intermitten t shor t t o power) .
I s cod e 6- 4 indicated ? Perfor
m th e appropriat e trouble -
shootin g fo r th e code .
Chec k th e rea r fail-saf e rela y (se e
sectio n 23 ).
I s th e rela y OK ?
Replace th e rea r fail-saf e relay .
Chec k th e modulato r wir e har -
ness :1. Disconnec t th e modulato r uni t14P connector .2. Visuall y chec k th e modulato r
wir e harness .
I s ther e a shor t t o power ? Replac
e th e modulato r wir e har -
nes s (o r repai r short) .
(T o pag e 19-75 )
Confir
m th e DT C tha t appear s first .
Proble
m verification :
Start th e engine .
With engin e running , AB S indi -cato r ligh t i s ON .With th e SC S servic e connec -
to r connecte d (se e pag e
19-40 ), DT C 6- 4 is indicated .
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