1996 ACURA RL KA9 relay

Component Locations

ABS CONTROL UNIT

MODULATOR UNIT
SERVICE CHECK CONNECTOR (2P)

ABS INSPECTION CONNECTOR (6P)

RIGHT-REAR WHEEL SENSOR

RIGHT-FRONT WHEEL

SENSOR CONNECTOR

RIGHT-FRONT

WHEEL SENSOR
LEFT-REAR WHEEL

SENSOR CONNECTOR

LEFT-REAR

WHEEL SENSOR

RIGHT-REAR WHEEL

SENSOR CONNECTOR

UNDER-HOOD

RELAY BOX B

UNDER-HOOD

FUSE/RELAY BOX
UNDER-DASH FUSE/RELAY BOX

LEFT-FRONT WHEEL SENSOR

LEFT-FRONT WHEEL

SENSOR CONNECTOR

GAUGE ASSEMBLY:

ABS INDICATOR LIGHT

UNDER-DASH FUSE/RELAY BOX:

METER

(7.5 A) FUSE
ABS B2

(15 A) FUSE

ABS B1

(20 A) FUSE

METER

(15 A) FUSE
BATTERY

(120 A) FUSE

ABS MOTOR (40 A) FUSE

IG SW (50 A) FUSE

UNDER-HOOD RELAY BOX C:

REAR FAIL-SAFE RELAY

METER RELAY

FRONT FAIL-SAFE RELAY
ABS
UNIT

(7.5 A) FUSE
STOP/HORN

(ISA) FUSE
ABS PUMP

MOTOR RELAY
UNDER-HOOD FUSE/RELAY BOX:

ECU

(20 A) FUSE

R/C MIRROR

(7.5 A) FUSEProCarManuals.com

Troubleshooting Precautions

ABS Indicator Light:

The ABS indicator light comes on for 3 seconds and then goes off when the control unit detects no problem during the ini-

tial diagnosis right after the engine starts. However, the ABS indicator light can stay on for up to 40 seconds when the

control unit starts to check for pump overrun, etc. during the initial diagnosis. The ABS indicator light comes on, and the

ABS control unit memorizes the diagnostic trouble code (DTC) under certain conditions.

The parking brake is applied for more than 30 seconds while the vehicle is being driven. (DTC 2-1)

The transmission downshifted excessively. (DTC 4-1, 4-2)

The vehicle loses traction, and the front wheels spin for more than 1 minute when starting from a stuck condition on a

muddy, snowy, or sandy road. (DTC 4-8)

Tire adhesion is lost due to excessive cornering speed. (DTC 5, 5-4, 5-8)

The vehicle is driven on an extremely rough road. (DTC 8-1)

The vehicle is interfered by strong radio waves (noise), for example, illegal radio, etc. (DTC 8-2)

NOTE: If there is any trouble in the system, the ABS indicator light comes on during driving.

Diagnostic Trouble Code (DTC):

When the control unit detects a problem and the ABS indicator light comes on, the control unit memorizes the DTC.

The control unit has three memory registers. When a problem occurs, the control unit stores the DTC in the first memory

register. If another problem occurs, or the same problem occurs again, the control unit moves the first DTC to the next

memory register, and stores the second DTC in the first register. If there's a third problem occurrence, the two existing

DTCs are moved up one register, and the third DTC is stored in the first register. If problems continue to occur, the oldest

problem is moved out of the last register and lost, and the most recent problem is stored in the first register. When the

same problem occurs three times, the same DTC is stored in all memory registers. (Refer to the Symptom-to-System

Chart for diagnostic period.)

The most recent DTC is indicated first, and the oldest DTC is indicated last.

The DTCs are erased from the control unit when the ABS control unit +B2 power supply or connector is disconnected.

The control unit's memory can be erased by disconnecting the ABS B2 fuse for more than 3 seconds.

Self-diagnosis:

There are three self-diagnoses described below.

Initial diagnosis: Performed right after the engine starts until the ABS indicator light goes off.

Regular diagnosis: Continuously performed (under some conditions) after the ABS indicator light goes off until the

engine stops.

Individual part/system diagnosis: Diagnosis about a specific part/system under its operating conditions.

The CPU (central processing unit) controls the following when it detects a problem during self-diagnosis:

Turns the ABS indicator light ON.

Turns the front and rear fail-safe relays off.

Stops the ABS control.

Stops the ABS pump. (The pump may work under some conditions.)

After the DTC is stored in the control unit, the CPU stops self-diagnosis.ProCarManuals.com

DTC Indication Pattern (When the ABS control unit detected a problem three times.):

Turn the ignition switch ON (II). The ABS indicator light comes on for 2 seconds to check the bulb.

The ABS control unit indicates the DTC 3 times.

If you miscount the blinking frequency or if you recheck the blinking frequency, turn the ignition switch OFF then

turn it ON (II) to cycle the ABS indicator light again.

4. Remove the SCS service connector.

NOTE: The Malfunction Indicator Lamp (MIL) will stay on after the engine is started if the SCS service connector is

connected.

5. Remove the ABS B2 (15 A) fuse in the under-hood fuse/relay box for at least 3 seconds to erase the ABS control unit's

memory.ProCarManuals.com

Troubleshooting
ABS Indicato r Ligh t Doe s No t G o Of f (N o DTC ) (cont'd )
(From pag e 19-45 )
Chec k th e under-hoo d fuse /
relay box :Measur e th e voltag e betwee n th e
under-hoo d fuse/rela y bo x 9 P
connecto r termina l No . 1 an dbody ground .
Is ther e batter y voltage ?
Chec k fo r a n ope n in th e +B 2 cir -
cuit :
1 . Disconnec t th e AB S contro l
unit 22 P an d 26 P connectors .2. Measur e th e voltag e betwee nthe AB S contro l uni t 26 P con -necto r termina l No . 1 3 an dbody ground .
I s ther e batter y voltage ? UNDER-HOO
D FUSE/RELA Y BO X
9 P CONNECTO R
Replac e th e under-hoo d fuse /
rela y box .
Wire sid e o f femal e terminal s
AB S CONTRO L UNI T 26 P CONNECTO R
Repair ope n in th e wir e betwee nthe under-hoo d fuse/rela y bo x
an d AB S contro l unit .
NOTE : Chec k wit h th e AB S contro l uni tconnector s disconnected .
Does th e AB S indicato r ligh tcom e on ? Repai
r shor t t o bod y groun d i n
th e wir e betwee n th e AB S indi -
cato r ligh t an d AB S contro l unit .
(T o pag e 19-47 )
Wire sid e o f femal e terminal s
Check fo r a shor t t o bod y groun d
i n th e WAR N circuit :
Turn th e ignitio n switc h O N (II) .
ProCarManuals.com

(From pag e 19-50 )
Remov e th e AB S pum p moto rrelay an d chec k it (se e sectio n 23 ).
I s th e rela y OK ?
Chec k th e AB S pum p moto r oper -
ation :
1 . Reliev e syste m pressur e (se e
pag e 19-97) .
2 . Connec t th e AB S pum p rela y
connecto r + B an d MOTO R ter -
minal s wit h a jumpe r wire for1 second .
Doe s th e pum p moto r run ?
Chec k th e MC K (moto r check ) cir -
cuit :
1 . Remov e th e jumpe r wire .
2. Disconnec t th e under-hoo dfuse/relay bo x 3 P connector .3. Tur n th e ignitio n switc h O N (II) .4. Measur e th e voltag e betwee nthe AB S pum p moto r rela yconnecto r moto r termina l an dbody ground .
Is ther e abou t 10V ?
(T o pag e 19-52 ) Replac
e th e AB S pum p moto r
relay .
NOTE : I f th e rela y i s stuc k ON , th e moto r ma y
b e damaged . Chec k th e pum p moto r opera -
tion.
UNDER-HOO D FUSE/RELA Y BO X
JUMPE R WIR E
NOTE : Us e a jumpe r wir e wit h a diamete r
large r tha n 2 m m (0.0 8 in) .
(T o pag e 19-53 )
T o chec k fo r a n ope n i n th e pum p
motor driv e circui t
ABS PUM P MOTO R RELA Y CONNECTO R
(T o pag e 19-54 )
T o chec k fo r a n ope n in th e MC K
circui t MOTO
R TERMINA L
AB S PUM P MOTO R RELA Y CONNECTO R
+
B TERMINA L
MOTO
R TERMINA L
ProCarManuals.com

Troubleshooting
DTC 1-2 : Pum p Moto r (cont'd )
(From pag e 19-51 )
Chec k fo r a n ope n in th e IG 2 cir -
cuit :
Measur e th e voltag e betwee n th e
under-hoo d fuse/rela y bo x 5 P
connecto r termina l No . 2 an dbody ground .
Is ther e batter y voltage ?
Chec k th e AB S pum p moto r rela y
operation :
1 . Connec t th e under-hoo d fuse /
rela y bo x 3 P connector.
2 . Instal l th e AB S pum p moto r
relay .
Doe s th e AB S pum p moto r
rela y operate ?
Chec k fo r a n ope n i n th e under -
hoo d fuse/rela y box :
Measur e th e voltag e betwee n th e
under-hoo d fuse/rela y bo x 5 P
connecto r termina l No . 1 an d
bod y ground .
I s ther e batter y voltage ?
Chec k fo r a n ope n in th e PM R cir -
cuit :
Measur e th e voltag e betwee n th e
AB S contro l uni t 22 P connecto r
termina l No . 2 1 an d bod y ground .
I s ther e batter y voltage ?
Reconnec t th e connector s prop -
erly , reliev e syste m pressur e an d
star t th e engine . I f DT C 1- 2 i s
store d again , replac e th e AB S
contro l unit . NOTE
: Th e AB S pum p moto r rela y coi l circui t
i s checke d beginnin g wit h thi s step .
UNDER-HOO D FUSE/RELA Y BO X5P CONNECTO R
Repair ope n in th e wir e betwee n
th e R/ C MIRRO R (7. 5 A ) fus e in th e
under-das h fuse/rela y bo x an d th e
under-hoo d fuse/rela y box . Wir
e sid e o f femal e terminal s
(T o pag e 19-55 )
T o chec k fo r a shor t t o bod y groun d
i n th e AB S pum p moto r rela y coi l cir -
cuit
NOTE : Th e AB S pum p moto r rela y coi l circui t
i s checke d fo r a n ope n beginnin g wit h thi s
step .
UNDER-HOO D FUSE/RELA Y BO X
5 P CONNECTO R
Replace th e under-hoo d fuse /
rela y box .
(Ope n circui t insid e th e box ) Wir
e sid e o f femal e terminal s
AB S CONTRO L UNI T 22 P CONNECTO R
Repai r ope n in th e wir e betwee n
th e under-hoo d fuse/rela y bo x
an d AB S contro l unit .
NOTE : Ad d brak e flui d i f th e flui d leve l i s
lowe r tha n th e MI N line . Wir
e sid e o f femal e terminal s
ProCarManuals.com

(From pag e 19-52 )
Chec k fo r a shor t i n th e under -
hoo d fuse/rela y box :
1 . Remov e th e AB S pum p moto r
relay.2. Disconnec t th e under-hoo d
fuse/rela y bo x 5 P connector .
3 . Chec k fo r continuit y betwee n
th e AB S pum p moto r rela y
connecto r PM R termina l an d
bod y ground .
I s ther e continuity ?
Chec k fo r a shor t i n th e PM R cir -
cuit :
1 . Disconnec t th e AB S contro l
uni t 22 P connector .
2 . Chec k fo r continuit y betwee n
termina l No . 2 1 an d bod y
ground .
NOTE:Short t o bod y groun d i n th e AB S pum p
moto r rela y coi l circui t i s checke d beginnin g
wit h thi s step .
I f th e moto r rela y coi l i s shorte d t o bod y
ground , th e moto r ma y b e damaged . Chec k
th e pum p moto r operation . UNDER-HOO
D FUSE/RELA Y BO X
PM R TERMINA L
Replac e th e under-hoo d fuse /
relay box .(Shor t circui t insid e th e box )
ABS CONTRO L UNI T 22 P CONNECTO R
I s ther e continuity ?
Repair shor t t o bod y groun d in th ewir e betwee n th e under-hoo d
fuse/rela y bo x an d AB S contro l
unit . Wir
e sid e o f femal e terminal s
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 .
ProCarManuals.com

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 .
ProCarManuals.com