ACURA RL KA9 1996 Service Repair Manual

Troubleshooting
Engine Coolan t Temperatur e (ECT ) Senso r
The blowe r moto r doe s no t ru n immediately , eve n thoug h th e engin e is full y warme d up . (NOTE : Th e temperatur e contro l
dia l mus t b e se t betwee n 61° F [18°C ] an d 89° F [32°C]. )
Does th e malfunctio n indica -
to r lam p com e on ?
Chec k fo r a n ope n in th e wire :
1 . Tur n th e ignitio n switc h OFF .
2 . Remov e th e climat e contro l
uni t (se e pag e 22-55 ), an d dis -
connec t th e 8 P an d 20 P con -
nectors .
3 . Disconnec t th e EC T senso r 2 P
connecto r (se e sectio n 11 ).
4 . Chec k fo r continuit y betwee n
th e No . 1 7 termina l o f th e 20 P
connecto r an d th e No . 2 ter -
mina l o f th e 2 P connector .
I s ther e continuity ?
Chec k fo r loos e wire s o r poo r
connection s a t th e climat e con -trol uni t 20 P connecto r an d a t
th e EC T senso r 2 P connector . I f
th e connection s ar e good , substi -
tut e a known-goo d climat e con -
trol unit , an d recheck . I f th esymptom/indicatio n goe s away ,
replac e th e origina l climat e con -
tro l unit . Se
e sectio n 11 .
CLIMATE CONTRO L UNI T 20 P CONNECTO R
Wir e sid e o f femal e terminal s
Repai r ope n in th e wir e betwee n
th e climat e contro l uni t an d th e
EC T sensor .
ECT SENSO R 2P CONNECTO R
Wir e side of femal e terminal s
Chec
k th e malfunctio n indicato r
lam p (MIL) .
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Climate Contro l Uni t
No heate r an d A/ C in eithe r man -
ua l o r AUT O modes .
Chec k th e No . 3 (7. 5 A ) fus e in th e
under-das h fuse/rela y box , an d
th e No . 5 6 (7. 5 A ) fus e i n th e
under-hoo d fuse/rela y box .
Ar e th e fuse s OK ?
Chec k fo r a n ope n in th e wire :
1 . Remov e th e climat e contro l
uni t (se e pag e 22-55 ), an d dis -
connec t th e 8 P an d 20 P con -
nectors .2. Tur n th e ignitio n switc h O N (II) .
3 . Measur e th e voltag e betwee n
th e No . 1 termina l o f th e 8 P
connecto r an d bod y ground .
I s ther e batter y voltage ?
Chec k fo r a shor t i n th e wire :
1 . Tur n th e ignitio n switc h OFF .
2 . Chec k fo r continuit y betwee n
th e No . 3 termina l o f th e cli -
mat e contro l uni t 8 P connec -
to r an d bod y ground .
I s ther e continuity ?
Chec k fo r a n ope n in th e wire :
Chec k fo r continuit y betwee n th e
No . 7 termina l o f th e climat e con -
tro l uni t 8 P connecto r an d bod y
ground .
Is ther e continuity ?
Chec k fo r loos e wire s o r poo r
connection s a t th e climat e con -
tro l uni t 8 P connector . I f th e con -
nection s ar e good , substitut e a
known-goo d climat e contro l unit ,
an d recheck . I f th e symptom/indi -
catio n goe s away , replac e th e
origina l climat e contro l unit .
Replac e th e fuse(s) , an d recheck .
CLIMATE CONTRO L UNI T 8 P CONNECTO R
Repai r ope n in th e wir e betwee n
th e No . 3 fus e an d th e climat e
contro l unit . Wir
e sid e o f femal e terminal s
Repai r shor t i n th e wir e betwee n
th e climat e contro l unit , th e ai r
mi x contro l moto r an d th e mod e
contro l motor .
Chec k fo r a n ope n i n th e wir e
betwee n th e climat e contro l uni t
an d bod y ground . I f th e wir e i s
OK , chec k fo r poo r groun d a t
G40 1 an d G402 .
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Troubleshooting
Radiator Fa n Contro l Senso r Circui t Ope n
Is ther e continuity ?
Chec k fo r a n ope n in th e wire :
Chec k fo r continuit y betwee n th e
No. 1 termina l o f th e radiato r fa ncontro l senso r 2 P connecto r an d
th e No . 6 termina l o f th e fa n con -
trol uni t 12 P connector .
Is ther e continuity ?
Tes t th e radiato r fa n contro l senso r
(se e Fa n Control s in sectio n 10) .
I s th e senso r OK ?
Chec k fo r loos e wire s o r poo r
connection s a t th e fa n contro l
uni t 12 P connector . I f th e con -
nection s ar e good , substitut e a
known-goo d fa n contro l unit ,and recheck . I f th e symptom /
indicatio n goe s away , replac e
origina l fa n contro l unit . FA
N CONTRO L UNI T 12 P CONNECTO R
Wir e sid e o f femal e terminal s
RADIATO R FA N CONTRO L SENSO R 2P CONNECTO R
Wir e sid e o f femal e terminal s
Repai r ope n i n th e wir e betwee n
th e radiato r fa n contro l senso r
an d th e fa n contro l unit .
Repai r ope n i n th e wir e betwee n
th e radiato r fa n contro l senso r
an d th e fa n contro l unit .
Replac e th e radiato r fa n contro l
sensor.
Both fan s d o no t ru n fo r engin e
coolin g (bu t the y bot h ru n wit h
the A/ C on) .
Chec k fo r a n ope n in th e wire :
1 . Disconnec t th e radiato r fa n
contro l senso r 2 P connecto r
and th e fa n contro l uni t 12 Pconnector .
2 . Chec k fo r continuit y betwee n
the No . 2 termina l o f th e 2 Pconnecto r an d th e No . 1 2 ter -
mina l o f th e 12 P connector .
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Radiator Fa n Contro l Senso r Circui t Shor t
NOTE : I t i s norma l fo r bot h fan s t o ru n a t hig h spee d whe n th e syste m pressur e i s
abov e 1,52 0 kP a (15. 5 kgf/cm2, 22 0 psi) , o r whe n th e engin e coolan t temperatur e i s
abov e 194° F (90°C) .
RADIATOR FA N CONTRO L SENSO R 2P CONNECTO R
I s ther e continuity ? Repai
r shor t i n th e wir e betwee n
th e radiato r fa n contro l senso r
an d th e fa n contro l unit . Wir
e sid e o f femal e terminal s
Tes t th e radiato r fa n contro l senso r
(se e Fa n Control s in sectio n 10 ).
I s th e senso r OK ? Replac
e th e radiato r fa n contro l
sensor.
Check fo r loos e wire s o r poo r con -
nection s a t th e fa n contro l uni t
12 P connector . I f th e connection s
ar e good , substitut e a known -
goo d fa n contro l unit , an d
recheck . I f th e symptom/indica -
tio n goe s away , replac e origina l
fa n contro l unit .
Chec
k fo r a n shor t i n th e wire :
1 . Disconnec t th e radiato r fa n
contro l senso r 2 P connecto r
and th e fa n contro l uni t 12 Pconnector .
2 . Chec k fo r continuit y betwee n
th e No . 2 termina l o f th e radi -
ato r fa n contro l senso r 2 P
connecto r an d bod y ground .
Bot
h fan s alway s ru n a t hig h
spee d fo r engin e cooling .
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Troubleshooting
A/C Pressur e Switc h (Middle )
Is ther e continuity ?
Chec k fo r a n ope n in th e wire :
Chec k fo r continuit y betwee n th e
No . 3 termina l o f th e A/ C pres -
sur e switc h 4 P connecto r an d
bod y ground .
I s ther e continuity ?
Chec k fo r a n ope n in th e wire :
1 . Disconnec t th e fa n contro l uni t
12P connector .2. Chec k fo r continuit y betwee nthe No . 2 termina l o f th e A/ C
pressur e switc h 4 P connecto r
an d No . 1 termina l o f th e fa n
contro l uni t 12 P connector .
I s ther e continuit y ?
Chec k fo r loos e wire s o r poo r con -
nection s a t th e fa n contro l uni t
12 P connector . I f th e connection s
ar e good , substitut e a known -
goo d fa n contro l unit , an d
recheck . I f th e symptom/indica -
tio n goe s away , replac e origina l
fa n contro l unit . NOTE
: I t i s norma l fo r bot h fan s t o ru n a t hig h spee d whe n th e syste m pressur e is abov e
1,52 0 kP a (15. 5 kgf/cm
2, 22 0 psi) , o r whe n th e engin e coolan t temperatur e is abov e 194° F(90°C) .
A/C PRESSUR E SWITC H
Replac e th e A/ C pressur e switch .
A/C PRESSUR E SWITC H 4P CONNECTO R
Chec k fo r a n ope n i n th e wir e
betwee n th e A/ C pressur e switc h
an d bod y ground . I f th e wir e is OK ,
chec k fo r poo r groun d a t G201 . Wir
e sid e o f femal e terminal s
Repai r ope n i n th e wir e betwee n
th e A/ C pressur e switc h an d th e
fa n contro l unit . FA
N CONTRO L UNI T 12 P CONNECTO R
Wir e sid e o f femal e terminal s
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Radiator Fa n
Radiato r fa n doe s no t ru n a t hig h
spee d (bu t condense r fa n run s a t
hig h speed , an d bot h fan s ru n a t
lo w speed) .
Check th e No . 3 (7. 5 A ) i n th e
underdas h fuse/rela y box , an d th e
No . 4 7 (2 0 A ) fus e i n th e under -
hoo d fuse/rela y box .
Ar e th e fuse s OK ?
Remov e th e radiato r fa n rela y
fro m th e under-hoo d rela y bo x C ,
an d tes t i t (se e pag e 22-64 ).
I s th e rela y OK ?
Chec k fo r a n ope n in th e wire :
Measur e th e voltag e betwee n th e
No . 3 termina l o f th e radiato r fa n
rela y 4 P socke t an d bod y ground .
I s ther e batter y voltage ?
Chec k fo r a n ope n in th e wire :
Connec t th e No . 1 an d No . 3 ter -
minal s o f th e radiato r fa n rela y4P socke t wit h a jumpe r wire .
Doe s th e radiato r fa n run ?
Chec k fo r a n ope n in th e wire :
1 . Disconnec t th e jumpe r wire .
2 . Tur n th e ignitio n switc h O N (II) .
3 . Measur e th e voltag e betwee n
th e No . 2 termina l o f th e radi-
ato r fa n rela y 4 P socke t an d
bod y ground .
I s ther e batter y voltage ?
Repai r ope n i n th e L T GRN/BL K
wir e betwee n th e radiato r fa n
rela y an d th e fa n contro l unit .
Replac e th e fuse(s) , an d recheck .
Replace th e radiato r fa n relay . RADIATO
R FA N RELA Y 4P SOCKE T
Repai r ope n in th e wir e betwee n
th e No . 4 7 fus e an d th e radiato r
fa n relay .
Repai r ope n in th e wir e betwee n
th e radiato r fa n rela y an d th e
radiato r fan .
JUMPE RWIRE
Repai r ope n in th e wir e betwee n
th e No . 3 fus e an d th e radiato r
fa n relay .
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Troubleshooting
Condenser Fa n
Condense r fa n doe s no t ru n a t
hig h spee d (bu t radiato r fa n run s
a t hig h speed , an d bot h fan s ru n
a t lo w speed) .
Chec k th e No . 3 (7. 5 A ) fus e i n
th e under-das h fuse/rela y box .
I s th e fus e OK ?
Remov e th e radiato r fa n mai n
rela y fro m th e under-hoo d rela y
bo x A , an d tes t i t (se e pag e
22-64 ).
Is th e rela y OK ?
Chec k fo r a n ope n in th e wire :
1 . Tur n th e ignitio n switc h O N (II) .
2 . Measur e th e voltag e betwee n
th e No . 3 termina l o f th e radi -
ato r fa n mai n rela y 5 P socke t
an d bod y ground .
I s ther e batter y voltage ?
Is ther e continuity ?
Repair ope n i n th e L T GRN/BL K
wir e betwee n th e radiato r fa n
mai n rela y an d th e fa n contro l
unit . Replac
e th e fuse , an d recheck .
Replac e th e radiato r fa n mai n
relay.RADIATO R FA N MAI N RELA Y 5 P SOCKE T
BLK/YE L
Repair ope n i n th e wir e betwee n
th e No . 3 fus e an d th e radiato r
fa n mai n relay .
Chec k fo r a n ope n i n th e wir e
betwee n th e radiato r fa n mai n
rela y an d bod y ground . I f the
wir e is OK , chec k fo r poo r groun d
atG301 .
Chec
k fo r a n ope n in th e wire :
1. Tur n th e ignitio n switc h OFF .2. Chec k fo r continuit y betwee n
th e No . 4 termina l o f th e radi -
ator fa n mai n rela y 5 P socke tand bod y ground .
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Both Fans Low Speed and Radiator Fan High Speed

Both fans do not run at low speed,

and radiator fan does not run at

high speed (but condenser fan

runs at high speed).

Check for an open in the wire:

1. Disconnect the radiator fan 2P

connector.

2. Turn the ignition switch ON (II)

and the A/C system on to

MAX COOL.

3. Measure the voltage between

the No. 2 terminal and body

ground.
RADIATOR FAN 2P CONNECTOR

Wire side of female terminals

Is there battery voltage?
Repair open in the wire between

the radiator fan relay, the radia-

tor fan main relay and the radia-

tor
fan.

Is there continuity?
Check for an open in the wire

between the radiator fan and

body ground. If the wire is OK,

check for poor ground at G302.
Check for an open in the wire:

1. Turn the ignition switch OFF.

2. Check for continuity between

the No. 1 terminal of the radi-

ator fan 2P connector and

body ground.

Replace the radiator fan motor.ProCarManuals.com

Troubleshooting
Both Fan s Lo w Spee d an d Condense r Fa n Hig h Spee d
Both fan s d o no t ru n a t lo w
speed , an d condense r fa n doe s
no t ru n a t hig h spee d (bu t radia -
to r fa n run s a t hig h speed) .
Chec k th e No . 3 (7. 5 A ) fus e i n th e
under-das h fuse/rela y box , an d th e
No . 5 0 (2 0 A ) fus e i n th e under -
hoo d fuse/rela y box .
Ar e th e fuse s OK ?
Remov e th e condense r fa n rela y
fro m th e under-hoo d rela y bo x A ,
an d tes t i t (se e pag e 22-64 ).
I s th e rela y OK ?
Chec k fo r a n ope n in th e wire :
Measur e th e voltag e betwee n th e
No . 1 termina l o f th e condense r
fa n rela y 4 P socke t an d bod y
ground .
I s ther e batter y voltage ?
Chec k th e condense r fan :
Connec t th e No . 1 an d No . 3 ter -
minal s o f th e condense r fa n rela y
4P socke t wit h a jumpe r wire .
Replac e th e fuse(s) , an d recheck .
Replac e th e condense r fa n relay .
CONDENSER FA N RELA Y 4 P SOCKE T
Repai r ope n i n th e wir e betwee n
th e No . 5 0 fus e an d th e conden -
se r fa n relay .
JUMPE RWIRE
Does th e condense r fa n run ? T
o pag e 22-4 5
T o pag e 22-4 6
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From pag e 22-4 4
Chec k fo r a n ope n in th e wire :
1 Disconnec t th e jumpe r wire .
2 . Disconnec t th e condense r fa n
2P connector .3. Chec k fo r continuit y betwee n
th e No . 3 termina l o f th e con -
dense r fa n rela y 4 P socke t an d
th e No . 2 termina l o f th e con -
denser fan 2 P connector .
I s ther e continuity ? CONDENSE
R FA N RELA Y 4 P SOCKE T
BLU
Repai r ope n i n th e wir e betwee n
th e condense r fa n rela y an d th e
condense r fan .
CONDENSE R FA N 2 P CONNECTO RWire sid e o f femal e terminal s
RADIATO R FA N MAI N RELA Y 5 P SOCKE T
I s ther e continuity ? Repai
r ope n i n th e wir e betwee n
th e condense r fa n an d th e radia -
to r fa n mai n relay .
Tes t th e radiato r fa n mai n rela y
(se e pag e 22-64 ).
Is th e rela y OK ?Replac e th e radiato r fa n mai nrelay .
Replac e th e condense r fa n motor .
Chec
k fo r a n ope n in th e wire :
1 . Remov e th e radiato r fa n mai n
relay fro m th e under-hoo drelay bo x A .
2 . Chec k fo r continuit y betwee n
th e No . 1 termina l o f th e con -
dense r fa n 2 P connecto r an d
th e No . 5 termina l o f th e radi -
ato r fa n mai n rela y 5 P socket .
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