1997 ACURA NSX Service Repair Manual

5. Check for continuity between the segments of the

commutator. If an open circuit exists between any

segments, replace the armature.

COMMUTATOR

SEGMENT

6. Place the armature on an armature tester. Hold a

hacksaw blade on the armature core.

ARMATURE TESTER
HACKSAW BLADE

ARMATURE

If the blade is attracted to the core or vibrates while

the core is turned, the armature is shorted. Replace

the armature.
7. With an ohmmeter, check that no continuity exists

between the commutator and armature coil core,

and between the commutator and armature shaft.

If continuity exists, replace the armature.

SHAFT

COIL CORE

COMMUTATORProCarManuals.com

Starting System

Solenoid Plunger Inspection

Check the contact points and face of the starter

solenoid plunger for burning, pitting or any other

defects. If surfaces are rough, recondition them with a

strip of #500 or #600 sandpaper.

CONTACT POINTS

SOLENOID

PLUNGER

POINT CONTACTING

FACE
Starter Field Winding Test

1. Check for continuity between the brushes. If

there's no continuity, replace the armature

housing.

2. Check for continuity between each brush and the

armature housing (ground).

If continuity exists, replace the armature housing.

BRUSHES

ARMATURE HOUSING

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Overrunning Clutch Inspection

1. Check if the overrunning clutch moves along the

shaft freely. If not, replace the overrunning clutch

assembly.

2. Check if the overrunning clutch locks in one direc-

tion and rotates smoothly in reverse. If it does not

lock in either direction or it locks in both directions,

replace the overrunning clutch assembly.

3. Check if the starter drive gear is worn or damaged.

If the gear is worn or damaged, replace the over-

running clutch assembly; the gear is not available

separately.

NOTE: Check the condition of the flywheel or tor-

que converter ring gear if the starter drive gear

teeth are damaged.
Starter Reassembly

Reassemble the starter in the reverse order of

disassembly.

1. Pry back each brush spring with a screwdriver,

then position the brush about halfway out of its

holder, and release the spring to hold it there.

2. Install the armature in the housing. Next pry back

each brush spring again, and push the brush down

until it seats against the commutator. Then release

the spring against the end of the brush.

3. Install the end cover on the brush holder.

END COVER

BRUSH HOLDER

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Ignition Syste m
Componen t Locatio n Inde x
IGNITIO N TIMIN G CONTRO L SYSTE M
Description , pag e 23-8 9
Inspection , pag e 23-9 1
Troubleshooting , sectio n 1 1
SERVIC E CHEC KCONNECTO R (2P )
(Connecto r color : BLU )
SPAR K PLU G (6 )
Inspection , pag e 23-9 6
NOIS E CONDENSE R
Test , pag e 23-9 7
TEST TACHOMETE R CONNECTO R
IGNITIO N CONTRO L MODUL E (ICM )
• Replacement , pag e 23-9 2
• Inpu t Test , pag e 23-9 3
• Troubleshooting , sectio n 1 1 IGNITIO
N COI L (6 )
• Removal , pag e 23-9 4
• Test , pag e 23-9 5 CRANKSHAF
T POSITION/CYLINDE R POSITIO N
(CKP/CYP ) SENSO R• Troubleshooting , sectio n 1 1
• Replacement , sectio n 5
SERVIC E LOO P
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Description ——————————————————\
——————————————————\
———
Ignition Timin g Control :
Th e programme d ignitio n use d i n thi s engin e provide s optimu m contro l o f ignitio n timing . A microcompute r determine s
th e timin g i n respons e t o engin e spee d an d manifol d vacuu m pressure . Th e inpu t signal s ar e transmitte d b y th e crank -
shaf t position/cylinde r positio n (CKP/CYP ) sensor , throttl e positio n (TP ) sensor , EC T sensor , an d MA P sensor . Thi s sys -
tem , no t dependen t o n a governo r o r vacuu m diaphragm , i s capabl e o f settin g lea d angle s wit h complicate d characteristic s
whic h canno t b e provide d b y conventiona l governor s o r diaphragms .
Basi c Contro l
Determinatio n of ignitio n timing/curren t duration :
Th e EC M ha s store d withi n i t th e optimu m basi c ignitio n timin g fo r operatin g condition s base d upo n engin e spee d an d in -
tak e manifol d pressure . Wit h compensatio n b y signal s fro m sensors , th e syste m determine s optimu m timin g fo r ambien t
condition s an d send s voltag e pulse s t o th e ICM .
Compensatio n o f Ignitio n Timing :
Compensatio n Ite m
Idlin g
Compensatio n a t warm-u p
Engin e coolan t
temperatur e compensatio nRelate
d Senso r an d Informatio n
CKP/CY P sensor , MA P senso r
Engin e coolan t temperatur e
(ECT) senso r
ECT senso r Descriptio
n
Ignitio n timin g i s controlle d t o th e targe t spee d
wit h compensatio n accordin g t o th e idlin g speed .
La g angl e i s adjuste d accordin g t o warm-u p con -
dition s t o brin g abou t a goo d balanc e betwee n
operatin g performanc e an d exhaus t ga s level .
Compensatio n fo r lea d angl e a t low coolan t
temperatur e an d la g angl e a t hig h coolan t
temperature .
Contro l a t Star t
Ignitio n timin g is fixe d a t 5 ° BTD C fo r cranking . Th e crankin g is detecte d b y th e CY P senso r (crankin g rpm ) an d starte r signal .
Misfirin g Detectio n
A s par t o f th e OB D II misfirin g detectio n system , eac h o f th e ignitio n coil s ha s a built-i n spar k plu g voltag e sensor . Thi s
senso r detect s th e lon g duratio n hig h voltag e whic h occur s i n cas e o f unfavorabl e combustio n o r misfiring . (Fo r details ,
se e sectio n 11 .)
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Ignition Timin g Inspectio n
SRS component s ar e locate d in thi s area . Revie w th e SR S
componen t locations , precautions , an d procedure s i n th e
SR S (sectio n 24 ) befor e performin g repair s o r service .
1 . Pul l ou t th e servic e chec k connecto r locate d unde r
th e middl e o f th e dash . Connec t th e BL U an d BRN /
BL K terminal s wit h th e SC S servic e connector .
2 . Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (A/ T i n o r position , M/ T i n neutral )
unti l th e radiato r fa n come s on , the n le t i t idle .
NOTE : I f yo u sto p th e engin e o r tur n th e ignitio n
switc h OF F afte r warm-u p wit h th e SC S servic e con -
necto r connected , th e engin e wil l idl e a t th e bas e
idl e speed . Tha t is , i t wil l no t b e controlle d b y th e
ECM . T o retur n t o th e norma l idl e speed , pres s th e
acclerato r peda l on e time .
SERVIC E CHEC K CONNECTO R (2P )
SC S SERVIC E CONNECTO R
07PAZ-001010 0
3. Chec k th e idl e spee d (se e pag e 23-92 ).
4 . Connec t a timin g ligh t t o th e servic e loop ; whil e th e
engin e idles , poin t th e ligh t towar d th e pointe r o n
the timin g bel t cover .
SERVIC E LOO P
TIMIN G LIGH T
5. Chec k th e ignitio n timin g wit h al l electrica l system s
ar e turne d OFF .
Ignitio n Timing : 15 ° ± 2° BTD C (RE D mark ) a t
Idl e Spee d (rpm) :
POINTE R
6. I f th e ignitio n timin g i s ou t o f spec , replac e th e ECM .
7 . Remov e th e SC S servic e connecto r fro m th e servic e
chec k connector .
CRANKSHAF T PULLE Y
RE
D MAR K
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Ignition Syste m
Idle Spee d Inspectio n
1. Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (A/ T i n o r position , M/ T i n neutral )
unti l th e radiato r fa n come s on , the n le t i t idle .
2 . Connec t a tachomete r t o th e tes t tachomete r con -
nector .
TEST
TACHOMETE R
CONNECTO R
3. Chec k th e idl e spee d wit h al l electrica l system s
turne d OFF .
Idl e Spee d (rpm) :
4 . Adjus t th e idl e spee d if necessar y (se e sectio n 11 ).
Ignitio n Contro l Modul e (ICM )
Replacemen t
1. Disconnec t th e 8 P an d 6 P connector s fro m th e igni -
tio n contro l modul e (ICM) .
2. Remov e th e tw o mountin g bolts , an d slid e th e IC M
out towar d th e fron t side . B e carefu l no t t o damag e
th e vacuu m hose s whe n removin g th e ICM .
MOUNTIN G BOLT S12 N- m(1.2 kgf-m , 9 Ibf-ft )
6P CONNECTO R
8P CONNECTO R
G103
SERVIC E LOO P
JUMP STAR TTERMINA L
TESTTACHOMETE RCONNECTOR
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Ignition Contro l Modul e (ICM ) Inpu t Tes t
Disconnec t th e 8 P connecto r fro m th e ignitio n contro l
modul e (ICM) .
Inspec t th e connecto r an d socke t terminal s t o b e sur e
they ar e al l makin g goo d contact .
I f th e terminal s ar e bent , loose , o r corroded , repai r
them as necessary , an d rechec k th e system .
I f th e terminal s loo k OK , mak e th e followin g inpu t
test s a t th e connector .
— If an y tes t indicate s a problem , fin d an d correc t th e
cause , the n rechec k th e system .
— If al l th e inpu t test s prov e OK , th e IC M mus t b e faul -
ty ; replac e it .
IC M
NOTE :
The tachomete r shoul d operat e normally .
See sectio n 1 1 whe n th e malfunctio n indicato r
lamp (MIL ) blinks .
I f necessary , perfor m a n inpu t tes t o n th e IC M
afte r finishin g th e fundamenta l test s fo r th e igni -
tio n syste m an d fue l an d emissio n systems .
WHT/GRN
WHT1BLK1
WHT/BLK
View fro m termina l sid e
WHT/RE D
BLK2 WHT/YE L
8P CONNECTO R
No.Wir eTes t conditio n Test: Desire d resul t Possible caus e if resul t i s no t obtaine d
1
2
3
4
5
6
7
8
BLK1
BLK2
WHT1
WHT/GR N
WHT/BLK
WHT/BLU1
WHT/YE L
WHT/RE D
Under al l condition s
Ignition switc h "O N
(ID"
Chec k fo r continuit y t o ground :
Ther e shoul d b e continuity .
Chec k fo r voltag e t o ground :
Ther e shoul d b e batter y
voltage . •
Poo r groun d (G103 )
• A n ope n i n th e wir e
• Blow n No . 1 3 (3 0 A ) fus e i n th e
engin e compartmen t fuse/rela y
box
• Fault y ignitio n coi l
• A n ope n i n th e wir e
23-9 3
WHT/BLU1
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