1997 ACURA NSX air condition

General Info
Specifications
Maintenance
Engine
Cooling
Fuel and Emissions
*Transaxle
SteeringSuspension
*Brakes (Including ABS)
*Body
*Heating, Ventilation and
Air Conditioning
*Body Electrical
*Engine Electrical
*SRS
1997-200 5 NSX Main Menu
As sections w/ * include SRS components,
special precautions are required when servicing.
ProCarManuals.com

Standards an d Servic e Limit s
Air Conditionin g — Sectio n 2 2
Electrica l — Sectio n 2 3
*1 : Whe n usin g a ne w belt , adjus t deflectio n o r tensio n t o ne w values . Ru n th e engin e fo r 5 minute s the n tur n it off .
Readjus t deflectio n o r tensio n to use d bel t values .
*2 : D o no t adjus t th e gap , replac e spar k plu g if i t i s ou t o f specification .
ProCarManuals.com

Pulsed Secondary Air Injection System Description

The air pump system is designed to advance the activation of the catalyst and to reduce the hydrocarbons (HC), carbon

monoxide (CO), and oxides of nitrogen (NOx) in the exhaust gas.

The system operates after the engine starts under the following conditions:

• The engine coolant temperature is between 0°C and 70°C (32°F and 158°F).

• The difference in engine coolant temperature is more than 20°C (36°F) between the time when the engine is started and

when the engine is stopped in the previous driving cycle.

AIR CONTROL

SOLENOID VALVE

AIR CONTROL

VALVE

WHT

AIR PUMP

RELAY
From

No. 5 BACK-UP LIGHTS

ALTERNATOR

TURN SIGNALS

(15 A) FUSE

From

AIR PUMP

(60 A) FUSE

AIR CONTROL VALVE

VACUUM TANK

AIR CONTROL VALVE

CHECK VALVE

When the engine is started, the air pump runs and sends fresh air to the air control valve. The air control valve allows the

fresh air to flow to the exhaust ports when its diaphragm is pulled by engine vacuum. It gets engine vacuum from the air

control solenoid, which is activated by the ECM. Once the fresh air flows into the exhaust ports near the exhaust valves, it

reacts with the exhaust gases, raising exhaust gas temperatures. This promotes faster warm-up of the catalytic converter.

The system operates for a maximum of 60 seconds, but the running time shortens in relation to the engine coolant tem-

perature and the intake air temperature. When the system is not operating, the air control solenoid and the air control

valve are closed to prevent exhaust gases from entering the system.
AIR PUMP

ELECTRICAL

CURRENT

SENSORProCarManuals.com

Troubleshooting Precaution s
EPS Indicato r Ligh t
Unde r norma l conditions , th e EP S indicato r i n th e gaug e assembl y come s o n whe n th e ignitio n switc h is turne d t o th e O N
(II ) position , the n goe s of f afte r th e engin e i s started . Thi s indicate s tha t th e bul b an d it s circuit s ar e operatin g correctly . I f
ther e i s an y troubl e i n th e system , th e EP S indicato r turn s o n durin g driving , an d th e powe r steerin g assis t i s turne d off .
Whe n th e EP S indicato r come s on , th e contro l uni t memorize s th e DTC . I n thi s case , th e contro l uni t doe s no t activat e th e
EP S syste m afte r th e engin e start s agai n bu t i t keep s th e EP S indicato r on .
Whe n a proble m is detected , th e EP S indicato r come s on . Unde r som e conditio n th e indicato r stay s o n unti l th e ignitio n switc h
i s turne d OFF . Unde r othe r conditions , however , th e indicato r goe s of f automaticall y whe n th e syste m return s to normal .
Fo r DTC s 2 3 an d 31 , th e indicato r goe s of f automaticall y whe n th e syste m return s t o normal . Fo r al l othe r codes , th e indicato r
stay s in unti l th e ignitio n switc h is turne d OFF .
Fo r DTC s 2 4 an d 25 , th e EP S indicato r goe s of f whe n th e syste m is O K afte r th e ignitio n switc h is turne d fro m OF F to O N
(ID .
Diagnosti c Troubl e Cod e (DTC )
• Th e lowes t DT C is indicate d first .
• Th e DTC s continu e blinkin g unti l th e ignitio n switc h i s turne d off .
• Th e DTC s ar e erase d fro m th e contro l uni t whe n th e EP S contro l uni t VB U powe r suppl y o r connecto r i s disconnected .
• Th e EP S syste m ca n b e rese t an d th e contro l unit' s memor y ca n b e erase d b y disconnectin g th e CLOC K (7. 5 A ) fus e fo r
mor e tha n te n second s (excep t DTC s 2 4 an d 25) .
Self-diagnosis :
The CP U (centra l processin g unit ) control s th e followin g whe n it detect s a proble m durin g self-diagnosis :
1 . Turn s th e EP S indicato r O N to aler t th e driver .
2 . Powe r assis t stops , an d norma l manua l steerin g operatio n resume s (excep t DT C 33) .
3 . Th e EP S contro l uni t memorize s th e diagnosti c troubl e cod e (DTC) .
4 . Afte r th e DT C is store d in th e contro l unit , th e CP U stop s self-diagnosis .
Troubleshooting :
• Befor e startin g th e troubleshooting , clea r th e DT C b y disconnectin g th e CLOC K (7. 5 A ) fus e fo r te n second s o r more ,
an d test-driv e th e vehicle . Chec k tha t th e sympto m o f th e troubl e appear s again , an d the n troubleshoot . I f th e proble m
i s a n intermitten t problem , th e syste m doe s no t becom e activ e afte r th e engin e start s eve n thoug h th e proble m is
solved .
• Whe n bot h EP S indicato r an d A/ T "D " indicato r com e on , perfor m th e A/ T troubleshootin g first .
• Whe n th e customer' s reporte d proble m canno t b e verifie d i n th e car , as k th e custome r abou t th e condition s whe n th e
EP S indicato r cam e ON , the n test-driv e th e ca r unde r thos e conditions , i f possible . I f th e EP S indicato r doe s no t com e
O N durin g th e test , chec k fo r loos e connection s o r poo r contact s a t th e connector s b y wigglin g th e harness , etc .
• Th e connecto r termina l number s ar e viewe d fro m th e wir e sid e fo r th e femal e terminal s an d fro m th e termina l sid e fo r
th e mal e terminals .
• Afte r th e repair , test-driv e th e ca r an d chec k tha t th e EP S indicato r doe s no t com e O N agai n durin g th e test . (Refe r t o
th e Symptom-to-Syste m Char t fo r diagnosti c period. )
ProCarManuals.com

Kickback

1. The motor operates when the ABS is functioning, and the fluid in the reservoir is forced out to the master cylinder,

causing kickback at the brake pedal.

Pump Motor

1. The pump motor operates when the ABS is functioning.

2. The ABS control unit checks the pump motor operation during initial diagnosis when the vehicle is started. You may

hear the motor operate at this time, but it is normal.

Brake Fluid Replacement/Air Bleeding

1. Brake fluid replacement and air bleeding procedures are the same as vehicles without ABS. To ease bleeding, start

with the front wheels.

Troubleshooting

1. The troubleshooting flowcharts procedures assume that the cause of the problem is still present and the ABS indicator

is still on. Following the flowchart when the ABS indicator does not come on can result in incorrect diagnosis.

2. Question the customer about the conditions when the problem occurred, and try to reproduce the same conditions

for troubleshooting.

Find out when the ABS indicator came on, such as during initial diagnosis, during ABS control, after ABS control,

when vehicle speed was at a certain speed, etc.

3. When the ABS indicator does not come on during the test-drive, but troubleshooting is performed based on the DTC,

check for loose connectors, poor contact at the terminals, etc. before you start troubleshooting.

4. After troubleshooting, erase the DTC and test-drive the vehicle. Be sure the ABS indicator does not come on.

5. The connector illustrations show the female terminals with a single outline and the male terminals with a double outline.

ABS Function Test

To simulate ABS operation and activate the solenoid valves and pump, use the Honda PGM Tester.

Connect the PGM Tester to the 16P Data Link Connector (DLC). When the System Select menu is displayed, select the ABS

Test Mode menu and follow the tester's prompts.ProCarManuals.com

Standards an d Servic e Limit s
Air Conditionin g — Sectio n 2 2
Electrica l — Sectio n 2 3
•1 : Whe n usin g a ne w belt , adjus t deflectio n o r tensio n to ne w values . Ru n th e engin e fo r 5 minute s the n tur n it off .Readjus t deflectio n o r tensio n t o use d bel t values .
*2 : D o no t adjus t th e gap , replace s spar k plu g i f i t i s ou t o f specification .
ProCarManuals.com

Standards an d Servic e Limit s
Air Conditionin g — Sectio n 2 2
Electrica l — Sectio n 2 3
*1 : Whe n usin g a ne w belt , adjus t deflectio n o r tensio n t o ne w values . Run the engin e fo r 5 minute s the n tur n i t off .
Readjus t deflectio n o r tensio n t o use d bel t values .
*2 : D o no t adjus t th e gap , replac e spar k plu g i f i t i s ou t o f specification .
ProCarManuals.com

Standards an d Servic e Limit s
Air Conditionin g — Sectio n 2 2
Electrica l — Sectio n 2 3
ProCarManuals.com