1996 ACURA RL KA9 radiator

Wiring/Connector Location s
RADIATOR FA N RELA Y
(Locate d i n th e under-hoo d rela y bo x C )
Test , pag e 22-6 4
RADIATO R FA N MAI N RELAY ,
CONDENSE R FA N RELAY ,
COMPRESSO R CLUTC H RELA Y
(Locate d i n th e under-hoo d rela y bo x A )
Test , pag e 22-6 4
RIGH T ENGIN E
COMPARTMEN T
WIR E HARNES S
A/ C PRESSUR E SWITC H
CONNECTO R
RADIATO R FA N
CONNECTO R
OUTSID E AI R TEMPERATUR E SENSO R
Replacement , pag e 22-6 1
Test , pag e 22-6 1 FA
N CONTRO L UNI T
(Locate d behin d th e PC M cover )
PCM COVE R
LEFT ENGIN E
COMPARTMEN T
WIR E HARNES S
COMPRESSO R CLUTC H
CONNECTO R
CONDENSE R FA N CONNECTO R
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A/C Pressure Switch

The A/C pressure switch consists of a High-Low pressure switch (A/C pressure switch A) and a Middle pressure switch

(A/C pressure switch B).

High-Low pressure switch

If the refrigerant pressure becomes too high (due to blockage), or too low (due to leakage), the A/C pressure switch

sends a signal to the fan control unit to prevent the compressor from operating.

ON

OFF

• Middle pressure switch

If the refrigerant pressure goes above or below 1,520 kPa (15.5 kgf/cm2, 220 psi), the A/C pressure switch sends a signal

to the fan control unit to change the speed of the condenser fan and radiator fan (High-Low).

290 kPa (3.0 kgf/cm2, 42 psi)

ON

OFF

1,230
kPa

(12.5 kgf/cm2,178 psi)
1,520
kPa

(15.5 kgf/cm2,220 psi)

MIDDLE

PRESSURE

SWITCH
HIGH-LOW

PRESSURE

SWITCHProCarManuals.com

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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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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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

Both Fans Low Speed

Both fans do not run at low speed

(but both fans run at high speed).

Check for an open in the wire:

1. Remove the radiator fan main

relay from the under-hood

relay box A.

2. Disconnect the radiator fan 2P

connector.

3. Check for continuity between

the No. 2 terminal of the radi-

ator fan main relay 5P socket

and the No. 2 terminal of the

radiator fan 2P connector.
NOTE: It is normal for both fans to run at high speed when the system pressure is above

1,520 kPa (15.5 kgf/cm2, 220 psi), or when the engine coolant temperature is above 194°F

(90°C).

RADIATOR FAN 2P CONNECTOR

Wire side of female terminals

RADIATOR FAN MAIN RELAY 5P SOCKET

Is there continuity?
Repair open in the wire between

the radiator fan main relay and

the radiator fan.

Replace the radiator fan main

relay.ProCarManuals.com

Relays

Test

There should be continuity between the No. 1 and No. 3

terminals when power and ground are connected to the

No. 2 and No. 4 terminals, and there should be no conti-

nuity when power is disconnected.

Radiator fan relay

Condenser fan relay

Compressor clutch relay
Blower motor relay

Blower motor high relay

There should be continuity between the No. 4 and No. 5

terminals when power and ground are connected to the

No. 1 and No. 3 terminals, and there should be continu-

ity between the No. 2 and No. 5 terminals when power

is disconnected.

Radiator fan main relayProCarManuals.com