1997 ACURA NSX lights

Emission Contro l Syste m
System Descriptio n
The emissio n contro l syste m include s tw o Thre e Wa y
Catalyti c Converter s (TWCs) , Exhaus t Ga s Recirculatio n
(EGR ) system , Positiv e Crankcas e Ventilatio n (PCV ) sys -
te m an d Evaporativ e Emissio n (EVAP ) Contro l system .
Th e emissio n contro l syste m is designe d t o mee t federa l
an d stat e emissio n standards .
Tailpipe Emissio n
1. Star t th e engine . Hol d th e engine at 3,00 0 rp m wit h
no loa d (A/ T in o r position , M/ T in neutral ) unti l
th e radiato r fa n come s on , the n le t i t idle .
2 . Connec t a tachometer .
3 . Chec k an d adjus t th e idl e speed , i f necessar y (se e
pag e 11-129 ).
4 . War m u p an d calibrat e th e C O mete r accordin g t o
th e mete r manufacturer' s instructions .
5 . Chec k idl e C O wit h th e headlights , heate r blower ,
rea r windo w defogger , coolin g fan , an d ai r condi -
tione r off .
NOTE : (Canada ) Pul l th e parkin g brak e leve r up .
Star t th e engine , the n chec k tha t th e headlight s ar e
off.
CO mete r shoul d indicat e 0.1 % maximum .
Inspection
any ope n flam e awa y fro m you r wor k area .
D
o no t smok e durin g thi s procedure . Kee p
ProCarManuals.com

Exhaust Gas Recirculation (EGR) System

The EGR system is designed to reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the EGR

valve and the intake manifold into the combustion chambers. It is composed of the EGR valve, EGR vacuum control valve,

EGR control solenoid valve, ECM and various sensors.

The ECM contains memories for ideal EGR valve lifts for varying operating conditions. The EGR valve lift sensor detects

the amount of EGR valve lift and sends the information to the ECM. The ECM then compares it with the ideal EGR valve lift

which is determined by signals sent from the other sensors. If there is any difference between the two, the ECM varies cur-

rent to the EGR control solenoid valve to regulate vacuum applied to the EGR valve.

EGR

VALVE

LIFT

SENSOR
INTAKE

MANIFOLD

EGR

CONTROL

SOLENOID

VALVE
To No. 5 BACK-UP

LIGHTS ALTERNATOR

TURN SIGNALS

(15 A) FUSE

-EGR

VACUUM

CONTROL

VALVE

(cont'd)
EGR

VALVE

VARIOUS

SENSORSProCarManuals.com

Evaporative Emission (EVAP) Controls

Description

The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The

system consists of the following components:

A. Evaporative Emission (EVAP) Control Canister

An EVAP control canister is used for the temporary storage of fuel vapor until the fuel vapor can be purged from the

EVAP control canister into the engine and burned.

B. Vapor Purge Control System

EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a port

on the throttle body. The purging vacuum is controlled by the EVAP purge control solenoid valve.

C. Fuel Tank Vapor Control System

When fuel vapor pressure in the fuel tank is higher than the set value of the EVAP two way valve, the valve opens and

regulates the flow of fuel vapor to the EVAP control canister.

From No. 5 BACK-UP

LIGHTS ALTERNATOR

TURN SIGNALS (15 A)

FUSE

FUEL TANK

EVAP VALVE
EVAP

BYPASS

SOLENOID

VALVE
VARIOUS

SENSORS

EVAP CONTROL

CANISTER

VENT SHUT VALVE

FUEL

TANK

PRESSURE

SENSOR
EVAP

TWO WAY

VALVE
EVAP CONTROL

CANISTER
EVAP PURGE

CONTROL

SOLENOID VALVE

(cont'd)
FUEL FILL

CAPProCarManuals.com

Pressure Switch

The pressure switch monitors the pressure accumulation (pressure from the pump) in the accumulator and is turned off

when the pressure becomes lower than a prescribed level. When the pressure switch is turned off, the switching signal is

sent to the ABS control unit. Upon receiving the signal, the ABS control unit activates the pump motor relay to operate the

motor. If the pressure doesn't reach the prescribed value, the ABS indicator light is turned on.

Operation

When the pressure in the accumulator rises, the Bourdon tube in the pressure switch deforms outwards. When the free

end of the Bourdon tube moves more than the prescribed amount, the micro-switch is activated by the force of the spring

attached to the sensing lever. When the pressure in the accumulator decreases due to anti-lock brake system operations,

the Bourdon tube moves in the direction opposite to the one described above, and the micro-switch is eventually turned

off. Upon receiving this signal, the ABS control unit activates the motor relay to operate the motor.

Power Unit

The power unit consists of a motor and a plunger-type pump. This unit transmits the revolution of the motor to the

plunger by way of an eccentric bearing and supplies high-pressure brake fluid to the accumulator by the effect of the

reciprocating movement of the plunger.

When the pressure in the accumulator drops below the prescribed pressure level, the pressure switch gives an OFF-signal.

The ABS control unit turns the motor relay ON to start the operation of the pump, upon the reception of this signal and a

signal from the wheel sensor that the vehicle is running at a speed greater than 6 mph (10 km/h). When the pressure in the

accumulator attains the prescribed pressure, the ABS control unit turns the motor relay OFF approximately three seconds

after the unit receives an ON-signal from the pressure switch. By this, the high-pressure in the accumulator is maintained.

The ABS control unit turns the pump off and lights the system indicator light if the accumulator pressure does not reach

the prescribed level after the pump has run continuously for 120 seconds.ProCarManuals.com

Front Bumper

Replacement

1. Loosen the mounting screw, then pull the right and left front turn signal lights out and disconnect the connectors.

2. Remove the skirt covers, then remove the bumper mounting bolts on each side, and lower skirt mounting bolt.

3. Lower the inner fender, then remove the bumper mounting nuts and the skirt mounting bolts from inside the front

fender on each side.

4. Lift and remove the front bumper.

NOTE:

• Disconnect the washer hose, horn connecters, and ambient sensor connector.

• An assistant is helpful when removing the front bumper.

• Take care not to scratch the front bumper.

5. Installation is the reverse of the removal procedure.

NOTE: Insert the bumper bracket hooks into the bumper bracket holes.ProCarManuals.com

Dashboard, Doo r an d Floo r
DRIVER' S DOO R PANE LABS CONTRO L UNI T
DAYTIM E RUNNIN GLIGHTS CONTRO LUNIT (Canada )
POWER WINDO WCONTRO L UNI T
SECURIT Y CONTRO L UNI T
POWE
R DOO R LOC K
CONTRO L UNI T
CIGARETT E LIGHTE RRELAYWire colors : YEL/RED ,
BLU/GRN , BRN/YEL . an d BL K FOO
T WEL L BAS S SPEAKE R
EPS CONTRO L UNI T(Behin d foo t wel lbass speaker )
RIGH T FRON T FLOO R
PANEL
SRS UNI T
STARTE R CU T RELA Y
Wir e colors : BLK/WHT ,
BLK/WHT , BLK/GRN ,
an d BLK/BL U
ProCarManuals.com

Relay and Control Unit Locations

Rear Bulkhead

PGM-FI MAIN RELAY
THROTTLE VALVE CONTROL

MOTOR RELAY

Wire colors: BLK,

YEL/BLK, GRN/RED,

and WHT/BLU

DASH LIGHTS

BRIGHTNESS

CONTROL UNIT
TRANSMISSION CONTROL

MODULE (TCM) (A/T)

PULSE UNIT (M/T)

ABS INDICATOR LIGHT

RELAY

Wire colors: BLU/WHT,

BLK, YEL/BLK, BLU/WHT
TCS CONTROL UNIT

FAN CONTROL

UNIT

ECMProCarManuals.com

Gauge Assembly

Bulb Locations

GAUGE LIGHTS (1.4 Wx 2)

SRS INDICATOR LIGHT (1.4 W)

RIGHT TURN SIGNAL INDICATOR LIGHT 11.4 W)

EPS INDICATOR LIGHT (1.4 W)

BRAKE SYSTEM LIGHT (1.4 W)

SEAT BELT REMINDER LIGHT (1.4 W)

IMMOBILIZER INDICATOR

LIGHT (1.4 W)

LOW FUEL INDICATOR

LIGHT (1.4 W)

GAUGE LIGHT

(1.4
W)
TCS INDICATOR LIGHT (1.96 W)

LEFT TURN SIGNAL INDICATOR LIGHT (1.4 W)

ABS

INDICATOR LIGHT (1.4 W)

CHARGING SYSTEM LIGHT (1.4 W)

MALFUNCTION

INDICATOR

LAMP (MIL)

(1.4
W)

CRUISE INDICATOR LIGHT

(1.96
W)
LOW OIL PRESSURE

INDICATOR

LIGHT (1.4 W)

GAUGE LIGHT

.4W)

GAUGE LIGHT

(3.0
W)
GAUGE LIGHT

GAUGE LIGHT HIGH BEAM INDICATOR (3.0 W)

(3.0 W) LIGHT (1.4 W)ProCarManuals.com