1995 ACURA TL park assist

Rack Guide Adjustment

NOTE: Perform rack guide adjustment with the wheels

in the straight ahead position.

1. Loosen the rack guide screw locknut with the spe-

cial tool, then loosen the rack guide screw.

RACK GUIDE SCREW
LOCKNUT

25 N-m

(2.5 kgf-m, 18 Ibf-ft)

1 3/4" CROWFOOT WRENCH

(Commercially available)

2. Tighten the rack guide screw to 25 N-m (2.5 kgf-m,

18 Ibf-ft), then loosen it.

3. Retighten the rack guide screw to 3.9 N-m (0.4 kgf-m,

2.9 Ibf-ft), then back it off to the specified angle.

Specified Return Angle: 20 ± 5°

4. Tighten the locknut while holding the rack guide

screw.

5. Check for tight or loose steering through the com-

plete turning travel.

6. Perform the following inspections (refer to the '95 - 98

Acura 2.5TL Service Manual, P/N 61SW504):

• Steering operation.

• Power assist with vehicle parked.ProCarManuals.com

ABS Functio n Tes t
1. Rais e th e ca r of f th e ground , an d suppor t i t wit h safet y
stands .
2. Chec k tha t ther e is n o brak e drag .
3 . Tur n th e ignitio n switc h O N (II) , an d confir m tha t th e
AB S indicato r ligh t come s on .
• I f th e AB S indicato r ligh t doe s no t com e on , follo w
th e troubleshootin g o n pag e 19-16 .
4 . Hond a PG M Tester : Connec t th e PG M Teste r a s
describe d i n th e PG M Teste r Anti-Loc k Brak e
Syste m (ABS ) Vehicl e Syste m Supplement . Follo w
th e tester' s prompt s instea d o f step s 5 throug h 1 1
o f thi s procedure .
AL B Checker : Wit h th e ignitio n switc h OFF , discon -
nec t th e AB S inspectio n connecto r (6P ) fro m th e
connecto r cove r locate d unde r th e glov e box , an d
connec t i t t o th e AL B checker . Continu e wit h step s 5
throug h 1 1 o f thi s procedure .
ALB CHECKE R07HAJ-SG0010 B
ABS
INSPECTIO NCONNECTO R (6P )
5. Shif t th e transmissio n t o position .
6 . Star t th e engin e an d releas e th e parkin g brake . 7
. Tur n th e Mod e Selecto r switc h t o "1" .
Monito r Light s
Powe r O NStar t Tes t
8. Pus h th e Star t Tes t switch .
Th e AB S indicato r ligh t shoul d no t com e o n whil e
th e Tes t i n Progres s ligh t i s on .
• I f th e AB S indicato r ligh t come s on , confir m th e
DT C an d perfor m th e appropriat e troubleshootin g
fo r th e code .
NOTE : D o no t tur n th e Mod e Selecto r switc h whe n
th e Tes t i n Progres s ligh t i s on . Damag e to th e AL B
checke r ca n result .
9 . Tur n th e Mod e Selecto r switc h t o "2" .
10 . Depres s th e brak e peda l firmly , an d pus h th e Star t
Test switch . Th e AB S indicato r ligh t shoul d no t com e
on whil e th e Tes t i n Progres s ligh t i s on . Ther e
shoul d b e kickbac k o n th e brak e pedal .
Hav e th e assistan t chec k tha t th e whee l controlle d b y
th e AB S ca n b e rotate d b y han d whe n ther e is kick -
back o n th e brak e pedal .
• I f th e AB S indicato r ligh t come s on , confir m th e
DT C an d perfor m th e appropriat e troubleshoot -
ing fo r th e code .
• I f th e AB S indicato r ligh t doe s no t com e o n an d
th e whee l controlle d b y th e AB S canno t b e rotat -
ed , chec k th e connectio n o f th e modulato r wir e
harnes s connectors . I f th e connection s ar e OK ,
replac e th e modulato r unit .
NOTE : Th e kickbac k shoul d occu r approximatel y 2 0
second s afte r th e Star t Tes t switc h i s pushed .
Th e AB S can be checke d wit h a brak e tester , too , b y
checkin g th e brak e torqu e fluctuatio n o f th e whee l
controlle d b y th e ABS .
11 . Tur n th e Mod e Selecto r switc h t o "3" , "4 " an d "5" .
Perfor m ste p 1 0 fo r eac h o f th e tes t mod e positions .
Mode Selecto r
ProCarManuals.com

System Descriptio n
This powe r steerin g syste m is speed-sensitive . It s mai n component s ar e a mechanica l spee d sensor , a rotar y valve-typ e
gearbox, an d a constan t volume , vane-typ e pump . Th e syste m regulate s th e powe r assis t accordin g to vehicl e speed , roa d
conditions , an d drivin g style . Th e amoun t o f powe r assis t change s linearl y fro m hig h assist , whe n drivin g a t lo w speed s o r
parking , t o lo w assist , whe n drivin g a t hig h speeds .
Fluid Flo w Diagra m
The flui d volum e fro m th e pump , whic h i s drive n b y th e cran k pulley , i s regulate d b y th e flo w contro l valv e buil t int o th e
pump . Th e regulate d flui d i s fe d t o th e valv e bod y uni t locate d outsid e th e pinio n shaf t o f th e steerin g gearbox . Th e flui d i s
regulate d t o th e prope r pressur e b y th e valve s i n th e valv e bod y uni t an d b y th e powe r steerin g spee d senso r befor e it
flow s t o th e powe r cylinder . Th e directio n o f th e flo w is determine d b y th e rotar y valve . Th e flui d the n returns to th e reser -
voi r throug h th e retur n passag e an d i s fe d t o th e pum p again .
To RESERVOI R
VALVE BOD Y UNI T
TORSIO N BA R
INPU T SHAF T
VALVE (SLEEVE )
RIGHT CYLINDE R PASSAG E
POWE R CYLINDE R
Steering Gearbo xLOW SPEE D FEE D PASSAG E
The steerin g gearbo x i s th e rack-and-pinio n type . Th e valv e bod y uni t consist s o f th e valv e bod y unit , wher e th e flui d pas -
sag e i s regulate d b y th e flui d pressure , an d th e assis t contro l valv e uni t whic h regulate s th e flui d passag e t o th e rotar y
valv e accordin g t o vehicl e speed .
ASSIST CONTRO L VALV E UNI T
STEERIN G RAC K VALV
E BOD Y UNI T
ToRESERVOI R
From PUM P
POWE R CYLINDE RCYLINDE
R LINE S ASSIS
T CONTRO L VALV E UNI T
PUM P
To POWE R STEERIN G
SPEE D SENSO R
PUM
P OUTLE T
HIGH-PRESSUR E
HIGH SPEE D
FEE D PASSAG E
POWER STEERIN G
SPEE D SENSO R
RESERVOI R
LEFT CYLINDE R
PASSAG E
ProCarManuals.com

System Description

System Operation (cont'd)

Hydraulic Control at Each Speed Range

When stopped:

When the vehicle is stopped with the engine idling, the fluid flow is shut off because the power steering speed sensor

rotor is not rotating. The standard pressure generated by the pressure control valve is applied to the assist control valve to

move the valve to the left. When the assist control valve is in this position, the orifice valve is closed. Therefore, the fluid

discharged from the pump is fed to the low speed valve of the valve body unit. Because the low speed valve has the small

chamfer and thereby the small opening angle, the large hydraulic pressure (steering rack thrust) results in the smallest

steering force (high assist).

HIGH SPEED FEED PASSAGE

LOW SPEED FEED PASSAGE
ASSIST CONTROL VALVE UNIT

POWER STEERING SPEED

SENSOR SIGNAL PRESSURE

HIGH SPEED

VALVE

SLEEVE

TORSION BAR

INPUT SHAFT

VALVE BODY UNIT

SENSOR ORIFICE

ASSIST VOLUME: LIGHT

STEERING WITH VEHICLE PARKED

ROAD SURFACE RESISTANCE

SMALL
LARGE
FLOW: O (ZERO)

LOW SPEED

VALVE

POWER STEERING SPEED

SENSOR AT A STOP
RESERVOIR
PUMP
FULL CLOSE

PRESSURE CONTROL VALVE
(HIGH)
ASSIST CONTROL

VALVEProCarManuals.com

Troubleshooting
General Troubleshootin g (cont'd )
Assist (excessivel y ligh t steering ) a thig h speed . Chec
k th e rac k guid e fo r prope r
adjustmen t (se e pag e 17-24 ).
Measur e forc e require d t o tur n
whee l wit h bypas s tub e join tinstalled , an d th e vehicl e parke d o n
dr y pave d surfac e (se e pag e 17-21 ). I
f th e proble m is no t correcte d b y
adjustin g th e rac k guide , adjus tthe fron t whee l alignmen t (se e
sectio n 18 ).
I f belo w th e specifications , chec k
th e powe r steerin g spee d sensor ,
assis t contro l valve , pressur e
contro l valv e an d valv e bod y uni t
fo r stickin g o r a clogge d orifice .
Shoc k o r vibratio n whe n whee l i s
turne d t o ful l lock . Chec
k th e rac k guid e fo r prope r
adjustmen t (se e pag e 17-24 ).
Rac k guid e is adjuste d properly .
Chec k th e bel t fo r slippag e an d
adjus t a s necessar y (se e pag e
17-23 ).
Rac k guid e wa s backe d of f exces -sively.
Adjus t th e rac k guide .
I f th e proble m is no t correcte d b y
adjustin g th e rac k guide , replac e
th e gearbox .
Steering whee l wil l no t retur nsmoothly . Chec
k cylinde r line s A an d B fo r
deformation .
A an d B cylinde r line s ar e nor -mal, chec k whee l alignmen t (se e
sectio n 18 ).
Whee l alignmen t i s normal .
Remov e th e gearbo x fro m th e
fram e an d measur e th e pinio n
torqu e o n th e gearbox . A
o r B cylinde r lin e i s deformed ;
replac e it .
Whee l alignmen t i s abnormal ,
adjus t a s needed .
I t shoul d b e 0. 7 - 1. 2 N- m (7 -
1 2 kgf-cm , 6-1 0 Ibf-in ) o r les s
wit h th e steerin g rac k i n th e
straigh t ahea d drivin g position .
1. 3 N- m (1 3 kgf-cm , 11. 3 Ibf-in )
wit h th e steerin g rac k i n an y
othe r position .
I f th e measurement s ar e ou t o f
specifications , adjus t th e rac k
guide .
I f th e proble m is no t correcte d b y
adjustin g th e rac k guide , replac ethe gearbox .
ProCarManuals.com

ABS Functio n Tes t
1. Rais e th e ca r of f th e ground , an d suppor t i t wit h safet y
stand s (se e sectio n 1 ).
2 . Chec k tha t ther e is n o brak e drag .
3 . Tur n th e ignitio n switc h O N (II) , an d confir m tha t th e
AB S indicato r ligh t come s on .
I f th e AB S indicato r ligh t doe s no t com e on , follo w
th e troubleshootin g o n pag e 19-60 .
4 . Hond a PG M Tester : Connec t th e PG M Teste r a s
describe d i n th e PG M Teste r Anti-Loc k Brak e
Syste m (ABS ) Vehicl e Syste m Supplement . Follo w
th e tester' s prompt s instea d o f step s 5 throug h 1 1
o f thi s procedure .
AL B Checker : Wit h th e ignitio n switc h OFF , discon -
nec t th e AB S inspectio n connecto r (6P ) fro m th e
connecto r cove r locate d unde r th e glov e box , an d
connec t i t t o th e AL B checker . Continu e wit h step s 5
throug h 1 1 o f thi s procedure .
ALB CHECKE R07HAJ-SG0010 BSee pag e 19-34 for othe r applicabl e checkers .
AB S INSPECTIO N
CONNECTO R (6P )
5. Shif t th e transmissio n t o [P ] position .
6 . Star t th e engin e an d releas e th e parkin g brake .
7. Tur n th e Mod e Selecto r switc h t o "1" .Monito r Light s
Power O N Star t Tes t Mod e Selecto r8. Pus h th e Star t Tes t switch .
Th e AB S indicato r ligh t shoul d no t com e o n whil e
th e Tes t i n Progres s ligh t i s on .
I f th e AB S indicato r ligh t come s on , confir m th e
DT C an d perfor m th e appropriat e troubleshootin g
fo r th e code .
NOTE : D o no t tur n th e Mod e Selecto r switc h whe n
the Tes t i n Progres s ligh t i s on . Damag e t o th e AL B
checke r ca n result .
9 . Tur n th e Mod e Selecto r switc h t o "2" .
10 . Depres s th e brak e peda l firmly , an d pus h th e Star t
Test switch . Th e AB S indicato r ligh t shoul d no t com e
on whil e th e Tes t i n Progres s ligh t i s on . Ther e
shoul d b e kickbac k o n th e brak e pedal .
Hav e th e assistan t chec k tha t th e whee l controlle d b y
th e AB S ca n b e rotate d b y han d whe n ther e i s kick -
bac k o n th e brak e pedal .
I f th e AB S indicato r ligh t come s on , confir m th e
DT C an d perfor m th e appropriat e troubleshoot -
in g fo r th e code .
I f th e AB S indicato r ligh t doe s no t com e o n an d
th e whee l controlle d b y th e AB S canno t b e rotated ,
chec k th e connectio n o f th e modulato r wir e har -
nes s connectors . I f th e connection s ar e OK , replac e
th e modulato r unit .
NOTE : Th e kickbac k shoul d occu r approximatel y 2 0
second s afte r th e Star t Tes t switc h is pushed .
Th e AB S ca n b e checke d wit h a brak e tester , too , b y
checkin g th e brak e torqu e fluctuatio n o f th e whee l
controlle d b y th e ABS .
11 . Tur n th e Mod e Selecto r switc h t o "3" , "4 " an d "5" .
Perfor m ste p 1 0 fo r eac h o f th e tes t mod e positions .
ProCarManuals.com