1997 ACURA NSX Service Repair Manual

NOTE: B e sur e th e batter y i s sufficientl y charge d (se e
page 23-68 ).
Connec t th e Su n VAT-4 0 (se e
pag e 23-102 ) an d tur n th e selec -
to r switc h to positio n 1 (starting) .
Star t th e engine , an d le t i t idl e
unti l i t reache s norma l operatin g
temperature .
Rais e th e engin e spee d t o 2,00 0
rpm , an d hol d i t there .
I s th e voltag e ove r 15. 1 V ?
Replace th e voltag e regulator .
Releas e th e accelerato r pedal ,
an d le t th e engin e idle .
Mak e sur e al l accessorie s ar e
turne d off . Tur n th e selecto r
switch to positio n 2 (charging) .
Remove th e inductiv e pick-up ,
an d zer o th e ammeter .
Attac h th e inductiv e pick-u p t o
th e B termina l wir e o f th e alterna -tor wit h it s arro w pointin g awa y
fro m th e terminal .
Rais e th e engin e spee d t o 2,00 0
rpm , an d hol d it there .
I s th e voltag e les s tha n 13. 9 V ?
Test th e batter y (se e pag e 23-68 ).
(T o page 23-104 )
(cont'd)
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Charging Syste m
Troubleshootin g (cont'd )
(From page 23-103 )
Apply a loa d wit h th e VAT-4 0
unti l th e batter y voltag e drop s t o
betwee n 12-13. 5 V .
I s th e amperag e 8 5 A or more ?
Wit h th e engin e spee d stil l a t
2,00 0 rpm , full-fiel d th e alter -
nator .
Tur n th e ignitio n switc h off .
Disconnec t th e 4- P connecto r
fro m th e alternator .
Tur n th e ignitio n switc h O N (II) .
Chec k fo r voltag e in th e YE L wir e
a t th e I G termina l an d i n th e
WHT/GR N wir e a t th e S termina l
o f th e 4- P connector .
I s ther e batter y voltag e in bot h
wires ?
Chargin g syste m is OK .
NOTE : Attac h a prob e to th e VAT-4 0 full-fiel d tes t
lead , an d inser t th e prob e int o th e full-fiel d acces s
hole a t th e bac k o f th e alternator . Switc h th e fiel d
selecto r t o " A (Ground) " positio n momentarily , an d
chec k th e amperag e reading .
CAUTION : Th e voltag e wil l ris e quickl y whe n th e
alternato r i s full-fielded . D o no t le t i t excee d 18 V
or yo u ma y damag e th e electrica l system .FULL-FIEL D ACCES S HOL E
END COVE R
REGULATO R(Located insid e th e en d cover )
Tes t an d repai r th e alternato r
(se e pag e 23-107 ).
IG (YEL )
S (WHT/GRN )
Repair ope n in th e YE L wir e o r th eWHT/GR N wire .
Is th e alternato r outpu t 8 5 A ormore ?
Replac e th e voltag e regulator .
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Alternator Replacemen t
1. Disconnec t th e negativ e cabl e fro m th e battery .
2 . Disconnec t th e 4 P connecto r fro m th e alternator .
3 . Remov e th e nu t an d th e BL K wir e fro m th e B
terminal .
BLK WIR ENUT 1 2 N- m(1.2 kgf-m , 9 Ibf-ft )
4P CONNECTO R
4. Remov e th e pulle y cove r fro m th e alternator .
PULLEY COVE R
5. Remov e th e nu t fro m th e adjustment-loc k bolt ,
loose n th e mountin g bol t an d th e adjustin g bolt ,
the n remov e th e bel t fro m th e pulley .
ADJUSTMENT-LOC KNUT45 N- m (4. 6 kgf-m , 3 3 Ibf-ft )
ADJUSTIN G BOL T8 N- m (0. 8 kgf-m , 5. 8 Ibf-ft )
ADJUSTMENT-LOC KBOLT
ALTERNATO RBRACKET
MOUNTIN G BOL T45 N- m (4. 6 kgf-m , 3 3 Ibf-ft )
6. Remov e th e adjustin g bolt , adjustment-loc k bol t
an d th e mountin g bolt , the n remov e th e alternato r
fro m th e bracket .
7 . Instal l th e alternato r i n th e revers e orde r o f
removal .
8. Adjus t th e alternato r bel t tensio n afte r installin g th e
alternato r (se e pag e 23-109 ).
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Charging Syste m
Alternato r Overhau l
NOTE: I t i s onl y necessar y t o separat e th e pulley , driv e
end housin g an d roto r whe n th e fron t bearin g need s
replacement .
Loosen th e locknu t wit h 1 0 m m an d 2 2 m m wrenche s
to remov e th e pulle y fro m th e rotor . I f necessary , us e a n
impac t wrench .
TERMINA L INSULATO R
PULLEY
22 m m BO XWRENC H
10 m m BO X WRENC H
PULLE Y LOCKNU T
11 5 N- m (11. 7 kgf-m , 8 5 Ibf-ft )
EN D COVE R
REAR HOUSIN G ASSEMBL Y
BRUS H HOLDE R
INSULATO R
BRUSHE S
Inspection , pag e 23-10 7
SPACE R RIN G
REA R BEARIN GDIOD
E (RECTIFIER ) ASSEMBL Y
Test , pag e 23-10 7
INSULATO R SLEEV E
BEARIN G RETAINE R
STATO R THROUG H BOL T D o no t disassemble .
STATO R ASSEMBLY/DRIV E EN D HOUSIN G
Test, pag e 23-10 8
PULLE Y LOCKNU T115 N- m(11. 7 kgf-m , 8 5 Ibf-ft )
ROTO RTest, pag e 23-10 8
CAUTION : D o no t ge t greas e
or oi l o n th e sli p rings .
FRON T BEARIN G
PULLEY
BRUSH HOLDE R
VOLTAG E REGULATO R
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Rectifier Test

NOTE: The diodes are designed to allow current to

pass in one direction while blocking it in the opposite

direction. Since the alternator rectifier is made up of

eight diodes (four pairs), each diode must be tested for

continuity in both directions with an ohmmeter that has

diode checking capability; a total of sixteen checks.

1. Check for continuity in each direction, between the

B and P, and between the E (ground) and P ter-

minals of each diode pair. All diodes should have

continuity in only one direction.

E (GROUND)

2. If any of the eight diodes fails, replace the rectifier

assembly. (Diodes are not available separately.)
Alternator Brush Inspection

1. Remove the end cover, then take out the brush

holder by removing its two screws.

2. Measure the length of the brushes with a vernier

caliper.

Alternator Brush Length:

Standard: 10.5 mm (0.41 in)

Service Limit: 3.5 mm (0.14 in)

ALTERNATOR BRUSHES

VERNIER CALIPER

If the brushes are less than the service limit,

replace the assembly.ProCarManuals.com

Charging System

Rotor Slip Ring Test

1. Check that there is continuity between the slip rings.

2. Check that there is no continuity between the slip

rings and the rotor or rotor shaft.

ROTOR SHAFT

SLIP RINGS
ROTOR

3. If the rotor fails either continuity check, replace the

alternator.
Stator Test

1. Check that there is continuity between each pair of

leads.

2. Check that there is no continuity between each lead

and the coil core.

LEADS

COIL CORE

3. If the coil fails either continuity check, replace the

alternator.ProCarManuals.com

Alternator Bel t Adjustmen t
Deflection Method :
1 . Appl y a forc e o f 9 8 N (1 0 kgf , 2 2 Ibf ) betwee n th e
alternato r an d crankshaf t pulley , an d measur e it s
deflection .
Deflection : 11-13. 5 m m (0.43-0.5 3 in )
NOTE : O n a brand-ne w belt , th e deflectio n shoul d
be 6- 8 m m (0.24-0.3 1 in ) befor e th e bel t ha s
had an y runnin g tim e o n th e engine .
ADJUSTIN G BOL T8 N- m (0. 8 kgf-m , 5. 8 Ibf-ft )
MOUNTIN G BOL T45 N- m (4. 6 kgf-m , 3 3 Ibf-ft )
ADJUSTMENT-LOC KNUT45 N- m (4. 6 kgf-m , 3 3 Ibf-ft )CRANKSHAF T PULLE Y
2. I f bel t deflectio n i s incorrect , loose n th e
adjustment-loc k nu t an d th e mountin g bolt .
3 . Tur n th e adjustin g bol t unti l bel t deflectio n i s cor -
rect , the n retighte n th e nu t an d bolt .
4 . Rechec k th e bel t tension . Tensio
n Gaug e Method :
1 . Attac h th e bel t tensio n gaug e t o th e belt , an d mea -
sur e bel t tension .
Tension : 45 0 - 65 0 N (4 5 - 6 5 kgf , 99-14 3 Ibf )
NOTE : O n a brand-ne w belt , th e tensio n shoul d b e
90 0 - 110 0 N (9 0 - 11 0 kgf , 19 8 - 24 3 Ibf ) befor e th e
bel t ha s ha d an y runnin g tim e o n th e engine .
MOUNTIN G BOL T45 N- m (4. 6 kgf-m , 3 3 Ibf-ft )
ADJUSTIN G BOL T8 N- m (0. 8 kgf-m , 5. 8 Ibf-ft )BELT TENSIO N GAUG E07JGG-001010 A
ADJUSTMENT-LOC KNUT45 N- m (4. 6 kgf-m ,33 Ibf-ft )CRANKSHAF T PULLE Y
2. I f bel t tensio n i s incorrect , loose n th e adjustment -
loc k nu t an d th e mountin g bolt .
3 . Tur n th e adjustin g bol t unti l bel t tensio n i s correct ,
the n retighte n th e nu t an d bolt .
4 . Rechec k th e bel t tension .
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Radiator an d Condense r Fa n Control s
Componen t Locatio n Inde x
RADIATO R FA N LO W RELA YWire colors : WHT/BLU ,RED, YEL/BLK , GRN/BL K
Test , pag e 23-11 9
A/C TRIPL E PRESSUR E
SWITC H
See sectio n 2 2
RADIATO R FA NRESISTO RTest, pag e 23-11 6 UNDER-HOO
D
RELAY BO X B
UNDER-HOO DRELAY BO X A
CLIMAT E CONTRO L UNI T
Troubleshooting , se e sectio n 2 2
RIGH T CONDENSE R
FA N MOTO R
Test , pag e 23-11 7
Replacement , se e sectio n 2 2 RADIATO
R FA N MOTO R
Test , pag e 23-11 7
Replacement , se e sectio n 5 LEF
T CONDENSE R FA N
MOTO R
Test , pag e 23-11 7
Replacement , se e sectio n 2 2
CONDENSE
R FA N RELA Y
Wir e colors : BLK ,
WHT/GRN , YEL/BLK ,
ORN/BLU
Test , pag e 23-11 9
RADIATOR FA N HIG H RELA Y
Wir e colors : WHT/BLU ,
BLK, YEL/BLK , BLU/RE D
Test , pag e 23-11 9
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