ACURA NSX 1997 Service Repair Manual

Half Lock-up

Lock-up Control Solenoid Valve A: ON Lock-up Control Solenoid Valve B: ON

Modulator pressure is released by solenoid valve B, causing modulator pressure in the left cavity of the lock-up control

valve to lower.

Also, modulator pressure in the left cavity of the lock-up timing valve B is low. Throttle B pressure is still low at this time,

so, lock-up timing valve B is kept on the right side by spring force.

With lock-up control solenoid valve B turned ON, the lock-up control valve is moved somewhat to the right side, causing

back pressure (F2) to lower. This allows move fluid (F1) to work on the lock-up clutch to engage the clutch. Back pressure

(F2), which still exists, prevents the clutch from engaging fully.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
Lock-up System (cont'd)
DescriptionProCarManuals.com

Full Lock-up

Lock-up Control Solenoid Valve A: ON Lock-up Control Solenoid Valve B: ON

When the vehicle speed further increases, the throttle B pressure is increased in accordance with the throttle opening.

The lock-up timing valve B overcomes the spring force and moves to the left side. Also this valve closes the fluid port

leading to the torque converter check valve.

Under this condition, the throttle B pressure working on the right end of the lock-up control valve becomes greater than

that on the left end (modulator pressure in the left end has already been released by the solenoid valve B); i. e., the lock-

up control valve is moved to the left side. As this happens, the torque converter back pressure is released fully, causing

the lock-up clutch to be engaged fully.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.ProCarManuals.com

Deceleration Lock-up

Lock-up Control Solenoid Valve A: ON Lock-up Control Solenoid Valve B: Duty Operation

The TCM switches the solenoid valve B to ON and OFF alternately at high speeds under certain conditions.

The slight lock-up and half lock-up regions are maintained so as to lock the torque converter properly.

NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
Lock-up System (cont'd)
DescriptionProCarManuals.com

ATF Cooler

The radiator is mounted at the front of the vehicle. The ATF cooler is installed directly on the transmission housing. The

ATF is cooled by the engine coolant.ProCarManuals.com

Component LocationsProCarManuals.com

<Engine Compartment>

LOCK-UP CONTROL SOLENOID

VALVE ASSEMBLY

MAINSHAFT SPEED SENSOR

LINEAR SOLENOID
ENGINE COOLANT TEMPERATURE (ECT)

SENSOR

THROTTLE POSITION (TP)

SENSOR

COUNTERSHAFT SPEED

SENSOR
SHIFT CONTROL SOLENOID

VALVE ASSEMBLY

VEHICLE SPEED SENSOR (VSS)

TRANSMISSION CONTROL

MODULE (TCM)

TCS CONTROL UNIT

ENGINE CONTROL MODULE

(ECM)ProCarManuals.com

Checking th e Diagnosti c Troubl e Cod e (DTC )
wit h a n OBDI I Sca n Too l o r th e Hond a PG M Teste r
When th e TC M sense s a n abnormalit y i n th e inpu t o r outpu t systems , th e indicato r ligh t i n th e gaug e assembl y wil l
blink . Whe n th e 16 P Dat a Lin k Connecto r (DLC ) (locate d t o th e lowe r lef t o f th e glov e compartment ) i s connecte d t o th e
OB D II Sca n Too l o r Hond a PG M Teste r a s shown , th e sca n too l o r teste r wil l indicat e th e Diagnosti c Troubl e Cod e (DTC )
when th e ignitio n switc h is turne d O N (II) .
Whe n th e indicato r ligh t ha s bee n reporte d on , connec t th e OB D II Sca n Too l conformin g t o SA E J197 8 o r Hond a PG M
Teste r t o th e DL C (16P ) a t th e lowe r lef t o f th e glov e compartment . Tur n th e ignitio n switc h O N (II) , an d observ e th e DT C
o n th e scree n o f th e OB D II Sca n Too l o r Hond a PG M Tester . Afte r determinin g th e DTC , refe r t o th e electrica l syste m
Symptom-to-Componen t Char t o n page s 14-8a and 14-9a .
NOTE : Se e th e OB D II Sca n Too l o r Hond a PG M Teste r user&#39; s manua l fo r specifi c instructions .
Troubleshootin g Procedure s
Some PGM-F I problem s wil l als o mak e th e indicato r ligh t com e on . Afte r repairin g th e PGM-F I system , disconnec t th e
CLOC K fus e (7. 5 A ) i n th e under-hoo d fuse/rela y bo x fo r mor e tha n 1 0 second s t o rese t th e TC M memory , the n recheck .
NOTE : Disconnectin g th e CLOC K fus e als o cancel s th e radi o prese t station s an d th e cloc k setting . Mak e not e o f th e radi o
preset s befor e removin g th e fus e s o yo u ca n rese t them .
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Checking th e Diagnosti c Troubl e Cod e (DTC )
wit h th e Servic e Chec k Connecto r an d Specia l Too t
Whe n th e TC M sense s a n abnormalit y i n th e inpu t o r outpu t systems , th e indicato r ligh t i n th e gaug e assembl y wil l
blink .
Whe n th e Servic e Chec k Connecto r (2P ) (locate d to th e lowe r righ t o f th e glov e compartment ) i s connecte d wit h th e specia l
tool a s shown , th e indicato r ligh t wil l blin k th e Diagnosti c Troubl e Cod e (DTC ) whe n th e ignitio n switc h is turne d o n (II) .
Whe n th e indicato r ligh t ha s bee n reporte d on , connec t th e Servic e Chec k Connecto r (2P ) t o th e specia l tool .
Then tur n th e ignitio n switc h o n (II ) an d observ e th e indicato r light .
Code s 1 throug h 9 ar e indicate d b y individua l shor t blinks , code s 1 0 throug h 2 0 ar e indicate d b y a serie s o f lon g an d shor t
blinks . On e lon g blin k equal s 1 0 shor t blinks . Ad d th e lon g an d shor t blink s together.to determine th e code . Afte r deter -
minin g th e code , refe r t o th e electrica l syste m Symptom-to-Componen t Char t o n page s 14-8a and 14-9a .
Some PGM-F I problem s wil l als o mak e th e indicato r ligh t com e on . Afte r repairin g th e PGM-F I system , disconnec t th e
CLOC K fus e (7. 5 A ) i n th e under-hoo d fuse/rela y bo x fo r mor e tha n 1 0 second s to rese t th e TC M memory , the n recheck .
NOTE : Disconnectin g th e CLOC K fus e als o cancel s th e radi o prese t station s an d th e cloc k setting .
Mak e not e o f th e radi o preset s befor e removin g th e fus e s o yo u ca n rese t them .
SCS SERVIC E CONNECTO R07PAZ-001010 0
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SRS component s ar e locate d i n 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 . Remov e th e sea t bac k panel s (se e sectio n 20 ).
2 . Remov e th e connecto r holde r fro m th e TC S contro l unit , an d disconnec t th e antenn a lead .
3 . Remov e th e TC S contro l unit .
NOTE : D o no t disconnec t th e connector s fro m th e TC S contro l unit .
Troubleshootin g Procedure s
4. Disconnec t th e B (22P ) connecto r fro m th e TCM , the n remov e th e TCM .
NOTE : D o no t disconnec t th e A (26P ) connecto r fro m th e TC M whil e removin g th e TCM .
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5. Inspec t th e circui t o n th e TC M accordin g t o th e troubleshootin g flowchar t wit h th e specia l tool s an d a digita l multime -
te r a s shown .
Ho w to us e th e Backprob e Se t
Connec t th e backprob e adapter s t o th e stackin g patc h cords , an d connec t th e cord s t o a multimeter . Usin g th e wir e
insulatio n a s a guid e fo r th e contoure d ti p o f th e backprob e adapter , gentl y slid e th e ti p int o th e connecto r fro m th e
wir e sid e unti l i t come s i n contac t wit h th e termina l en d o f th e wire .
BACKPROB E SE T07SAZ-001000 A(Two required )
TCM Rese t Procedur e
1. Tur n th e ignitio n switc h OFF .
2. Remov e th e No . 3 3 CLOC K fus e (7. 5 A ) fro m th e under-hoo d fuse/rela y bo x fo r 1 0 second s t o rese t th e TCM .
NOTE :
• Disconnectin g th e No . 3 3 CLOC K fus e als o cancel s th e radi o prese t station s an d cloc k setting . Mak e not e o f th e
radi o preset s befor e removin g th e fus e s o yo u ca n rese t them .
• Th e TC M memor y canno t b e cleare d b y usin g th e OB D II sca n Too l o r Hond a PG M Tester ; b e sur e t o remov e th e
CLOC K fus e to rese t th e TCM .
Fina l Procedur e
NOTE : Thi s procedur e mus t b e don e afte r an y troubleshooting .
1. Tur n th e ignitio n switc h OFF .
2. Rese t th e TCM .
3 . Disconnec t th e OB D II Sca n Too l o r Hond a PG M Teste r fro m th e Dat a Lin k Connector , o r remov e th e specia l too l fro m
th e Servic e Chec k Connector .
4 . Tur n th e ignitio n switc h O N (II) , an d se t th e radi o preset s an d cloc k setting .
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