1991 ACURA NSX Service Repair Manual

In-car Temperature Sensor
Removal
The in-car temperature sensor assembly includes a
small fan (aspirator fan) to draw air past the sensor (see
page 22-66('93-'96), 91('91-'92)).

SRS components are located in this area. Review the SRS

component locations, precautions, and procedures in the

SRS section (24) before performing repairs or service.

1. Remove the center console panel (see page 22-54).
2. Remove the two screws and the in-car temperature sensor from the under side of the center console

panel. Be careful not to damage the center console

panel.

IN-CAR TEMPERATURE

SENSOR

UNDER SIDE OF CENTER
CONSOLE PANEL
Test
Compare the resistance reading between the No, 1 and No. 2 terminals of the in-car temperature sensor with
specifications shown in the following graph: It should

be within specification.

TEMPERATURE

CAUTION: The sensor uses a thermistor which can
be damaged if high current is applied to it during test-
ing. Therefore, use a circuit tester that puts out a
measuring current of 1 mA or less.ProCarManuals.com

Outside Ai r Temperatur e Senso r
Remova l
Remove th e screw , disconnec t th e connector , an d
remov e th e outsid e ai r temperatur e sensor . B e carefu l
no t t o damag e th e fron t grill e an d fron t bumper .
OUTSIDE AI RTEMPERATUR ESENSOR
Test
Compar e th e resistanc e readin g betwee n th e terminal s
o f th e outsid e ai r temperatur e senso r wit h specifica -
tions show n in th e followin g graph : I t shoul d b e withi n
specification .
NOTE : Di p th e senso r i n ic e water , an d measur e th e
resistance . The n pou r ho t wate r o n th e sensor , an d
chec k fo r chang e i n resistance .
CAUTION : Th e senso r use s a thermisto r whic h
ca n b e damage d if hig h curren t i s applie d to it dur -
in g testing . Therefore , us e a circui t teste r tha t put s
out a measurin g curren t o f 1 m A o r less .
ProCarManuals.com

Sunlight Sensor

Removal

With a small screwdriver, carefully pry the sunlight sen-

sor out of the dashboard and disconnect its connector.

Protect the dashboard; cover it with a shop towel before

you pry against it.

SUNLIGHT

SENSOR
Test

Measure the voltage between the terminals with the sen-

sor out of direct sunlight.

• With the connector connected (probe the back of it):

1.4 ± 0.2 V

• With the connector disconnected: 0.1 — 0.2 VProCarManuals.com

Heater Core Temperature Sensor

Removal

Disconnect the connector, remove the clamp and the

heater core temperature sensor.

CLAMP

HEATER CORE

TEMPERATURE

SENSOR
Compare the resistance reading between the terminals

of the heater core temperature sensor with specifica-

tions shown in the following graph: It should be within

specification.

NOTE: Dip the sensor in ice water, and measure the

resistance. Then pour hot water on the sensor, and

check for change in resistance.

CAUTION: The sensor uses a thermistor which

can be damaged if high current is applied to it

during testing. Therefore, use a circuit tester

that puts out a measuring current of 1 mA or

less.
TestProCarManuals.com

Evaporator Temperatur e
Sensor
Remova l
Give th e evaporato r temperatur e senso r a quarte r turn ,
then pul l ou t t o remov e it .
EVAPORATO RTEMPERATUR E SENSO R
Test
Compar e th e resistanc e readin g betwee n th e terminal s
o f th e evaporato r temperatur e senso r wit h specificatio n
shown i n th e followin g graph : I t shoul d b e withi n
specification .
NOTE : Di p th e senso r i n ic e water , an d measur e th e
resistance . The n pou r ho t wate r o n th e sensor , an d
chec k fo r chang e i n resistance .
CAUTION : Th e senso r use s a thermisto r whic h
ca n b e damage d if hig h curren t i s applie d t o it
durin g testing . Therefore , us e a circui t teste r
tha t put s ou t a measurin g curren t o f 1 m A o r
less .
ProCarManuals.com

Aspirator Fa n
Tes t
Connec t batter y powe r t o th e No . 3 termina l o f th e
aspirato r fan , an d connec t groun d to th e No . 4 terminal .
Th e aspirato r fa n shoul d run .
Rela y
Test
Ther e shoul d b e continuit y betwee n th e C an d D
terminals .
Ther e shoul d b e continuit y betwee n th e A an d B ter -
minal s whe n powe r an d groun d ar e connecte d to th e C
an d D terminals .
Ther e shoul d b e n o continuit y whe n powe r i s
disconnected .
ProCarManuals.com

Blower Unit

Replacement

1. Remove the spare tire (refer to Owner's manual).

2. Remove the spare tire holder.

CORROSION RESISTANT BOLT

6 x 1.0 mm

10 N-m (1.0 kg-m, 7 Ib-ft)

SPARE TIRE

HOLDER

3. Disconnect the cables from the battery, loosen the

hold-down bracket nuts, and remove the hold-

down bracket. Then, remove the battery.

BATTERY

HOLD-DOWN

BRACKET
4. Remove the under-hood relay box A and the water

drain duct. Disconnect the connectors from the

blower motor, power transistor and recirculation

control motor.

CORROSION RESISTANT BOLT

6 x 1.0 mm

10 N-m (1.0 kg-m, 7 Ib-ft)

WATER

DRAIN

DUCT

BLOWER MOTOR,

POWER TRANSISTOR,

and RECIRCULATION CONTROL

MOTOR CONNECTORS 6 x 1.0 mm

10 N-m (1.0 kg-m, 7 Ib-ft)

5. Remove the mounting bolts, then remove the blower

unit.

CORROSION RESISTANT BOLT

BLOWER

UNIT

6 x 1.0 mm

10 N-m (1.0 kg-m, 7 Ib-ft)

6. Install the blower unit in the reverse order of

removal, then make sure it runs and doesn't leak

any
air.
UNDER-HOOD

RELAY

BOX AProCarManuals.com

Blower Uni t
Overhau l
RECIRCULATIO N
CONTRO L MOTO R BLOWE
R MOTO R
POWERTRANSISTO R
ProCarManuals.com