1995 ACURA TL service

Data
Description

Operating Value
Freeze Data

HO2S

Feedback

Loop Status
Loop status is indicated as "open" or "closed".

Closed: Based on the HO2S output, the ECM deter-

mines the air/fuel ratio and controls the amount of

injected fuel.

Open: Ignoring HO2S output, the ECM refers to signals

from the TP, MAF, and ECT sensors to control the

amount of injected fuel.
At idle speed: closed

Short Term

Fuel Trim
The air/fuel ratio correction coefficient for correcting

the amount of injected fuel when H02S feedback is in

the closed loop status. When the signal from the H02S

is weak, short term fuel trim gets higher, and the ECM

increases the amount of injected fuel. The air/fuel ratio

gradually gets richer, causing a higher HO2S output.

Consequently, the short term fuel trim is lowered, and

the ECM reduces the amount of injected fuel. This

cycle keeps the air/fuel ratio close to the stoichiometric

ratio when in closed loop status.
±20%

Long Term

Fuel Trim
Long term fuel trim is computed from short term fuel

trim and indicates changes occurring in the fuel supply

system over a long period.

If long term fuel trim is higher than 1.00, the amount of

injected fuel must be increased. If it is lower than 1.00,

the amount of injected fuel must be reduced.
±20%

Intake Air

Temperature

(IAT)
The IAT sensor converts intake air temperature into

voltage and signals the ECM. When intake air tempera-

ture is low, the internal resistance of the sensor

increases, and the voltage signal is higher.
With cold engine:

Same as ambient temper-

ature and ECT

Throttle

Position
Based on the accelerator pedal position, the opening

angle of the throttle valve is indicated.
At idle speed:

approx. 10%

Ignition

Timing
Ignition timing is the ignition advance angle set by the

ECM. The ECM matches ignition timing to the driving

conditions.
At idle speed: 15° ±2°

BTDC with the SCS service

connector connected.

Calculated

Load Value

(CLV)
CLV is the engine load calculated from the MAF data.
At idle speed:

14-27%

At 2,500 rpm with no load:

13-26%ProCarManuals.com

Fuel Supply System

Fuel Pressure

Relieving (models with service bolt)

Before disconnecting fuel pipes or hoses, release pres-

sure from the system by loosening the 6 mm service

bolt on top of the fuel filter.

Do not smoke while working on the fuel system.

Keep open flames or sparks away from your work

area.

• Be sure to relieve fuel pressure while the ignition

switch is off.

1. Make sure you have the anti-theft code for the radio,

then write down the frequencies for the radio's pre-

set buttons.

2. Disconnect the battery negative cable from the bat-

tery negative terminal.

3.
Remove
the
fuel
fill
cap.

4. Use a box end wrench on the 6 mm service bolt at

the fuel filter while holding the special banjo bolt

with another wrench.

5. Place a rag or shop towel over the 6 mm service bolt.

6. Slowly loosen the 6 mm service bolt one complete

turn.

SERVICE

BOLT

12 N-m

(1.2 kgf-m, 8.7 Ibf-ft)

SHOP TOWEL

FUEL FILTER
NOTE:

• A fuel pressure gauge can be attached at the 6 mm

service bolt hole.

• Always replace the washer between the service bolt

and the special banjo bolt whenever the service bolt

is loosened.

• Replace all washers whenever the bolts are removed.

Relieving (models without service bolt)

Before disconnecting fuel pipes or hoses, release pres-

sure from the system by loosening the 12 mm banjo

bolt on top of the fuel filter.

• Do not smoke while working on the fuel system.

Keep open flames or sparks away from your work

area.

• Be sure to relieve fuel pressure while the ignition

switch is off.

1. Make sure you have the anti-theft code for the radio,

then write down the frequencies for the radio's pre-

set buttons.

2. Disconnect the battery negative cable from the bat-

tery negative terminal.

3.
Remove
the
fuel
fill
cap.

4. Use a box end wrench on the 12 mm banjo bolt at

the fuel filter while holding the fuel filter with anoth-

er wrench.

5. Place a rag or shop towel over the 12 mm banjo bolt.

6. Slowly loosen the 12 mm banjo bolt one complete

turn.

12 mm

BANJO BOLT

33 N-m

(3.4 kgf-m, 25 Ibf-ft)

SHOP TOWEL

FUEL FILTER

NOTE: Replace the washers whenever the 12 mm

banjo bolt is loosened or removed.

11-124ProCarManuals.com

Fuel Supply System

Fuel Filter (cont'd)

Models with service bolt:

SPECIAL BOLT

27
N-m
(2.8
kgf-m,
20
Ibf-ft)

SERVICE BOLT

12N-m(1.2kgf-n

8.7
Ibf-ft)

WASHERS

Replace.

37
N-m

(3.8
kgf-m,

27
Ibf-ft)

9.8
N-m

(1.0
kgf-m,
7.2
Ibf-ft)

Models without service bolt:

9.8
N-m

(1.0
kgf-m,
7.2
Ibf-ft)
12mm

BANJO BOLT

33
N-m
(3.4
kgf-m,

25
Ibf-ft)

WASHER

Replace.

37
N-m

(3.8
kgf-m,

27
Ibf-ft)ProCarManuals.com

Description

The electronic control system consists of the Transmission Control Module (TCM), sensors, a linear solenoid, and four

solenoid valves.

Shift and lock-up are electronically controlled for comfortable driving under all conditions.

The TCM is located below the dashboard, behind the glove box on the passenger's side.

TCM

Linear Solenoid

Shift Control

Solenoid Valve A

Shift Control

Solenoid Valve B

Lock-up Control

Solenoid Valve A

Lock-up Control

Solenoid Valve B

Engine Speed Signal

Brake Switch Signal

Mainshaft Speed Sensor

Signal

Countershaft Speed

Sensor Signal

Vehicle Speed Sensor

Signal

Indicator Light

Self-Diagnosis Signal
Electronic Control System

Shift Control

Lock-up Control
Throttle Position

Sensor Signal

Engine Coolant

Temperature

Sensor Signal

Service Check

Connector

Barometric

Pressure Sensor

INTERLOCK

CONTROL UNIT

Self-Diagnosis

FunctionProCarManuals.com

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 l
Whe n th e TC M sense s a n abnormalit y in 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 (locate d unde r th e das h o n th e passenge r side ) i s connecte d wit h th e specia l too l 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 wit h th e specia l tool .
Then tur n o n (II ) th e ignitio n switc h an d observ e th e indicato r light .
GAUG E ASSEMBL YSERVICE CHEC KCONNECTO R (2P )
INDICATO RLIGHT
SCS SERVIC E CONNECTO R07PAZ- 001010 0
Codes 1 throug h 9 ar e indicate d b y individua l shor t blinks , code s 1 0 throug h 1 8 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 togethe r t o determin e th e code . Afte r deter -
minin g th e code , refe r t o th e electrica l syste m Symptom-t o Componen t Char t o n page s 14-5 6 an d 14-57 .
short
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
BAC K U P RADI O fus e (1 0 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 BAC K U P RADI O fus e als o cancel s th e radi o anti-theft code, prese t station s an d th e cloc k setting .
Ge t th e customer' s cod e number , an d 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 .
See DTC 1
See DTC 2
See DTC1 4
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Troubleshooting Procedure s
(cont'd)
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 in th e
SR S (sectio n 24 ) befor e performin g repair s o r service .
1. Remov e th e glov e bo x fro m th e dashboard .
CLIP
GLOV E BO X
5. 0 m m BOLT S
2.Remov e th e AB S contro l uni t mountin g bolts , an d
tur n th e AB S contro l uni t over . Disconnec t th e radi -
ato r fa n time r contro l uni t connecter .
NOTE: D o no t disconnec t th e connector s fro m th e
AB S contro l unit .
ABS CONTRO LUNIT
RADIATO R FA N
CONTRO L
MODULE CONNECTO R
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m ,
7. 2 Ibf-ft )
3. Remov e th e contro l uni t bracket , the n remov e th e
TCM .
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m , 7. 2 Ibf-ft )
WIR E HARNES S
CONNECTO R
STUD BOL T
CONTRO L UNI TBRACKE T
TCMFLANG ENUT9.8 N- m (1. 0 kgf-m ,
7. 2 Ibf-ft )
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Transmission Contro l Modul e (TCM )
Replacemen t
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 . Remov e th e glov e bo x fro m th e dashboard .
CLIP
GLOV E BO X
2.
5. 0 m m BOLT S
Remov e th e AB S contro l uni t mountin g bolts , an d
tur n th e AB S contro l uni t over . Disconnec t th e radi -
ato r fa n time r contro l uni t connector .
NOTE : D o no t disconnec t th e connector s fro m th e
AB S contro l unit .
ABS CONTRO LUNIT
RADIATO R FA N
TIME R CONTRO L
UNIT CONNECTO R
6 x 1. 0 m m9.8 N- m(1.0 kgf-m , 7. 2 Ibf-ft )
3. Remov e th e contro l uni t bracket , the n remov e th e
TCM . Disconnec t th e connector s an d replac e th e
TCM .
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m , 7. 2 Ibf-ft )
WIR E HARNES S
CONNECTO R
STUD BOL TFLANG E NU T
9. 8 N- m (1. 0 kgf-m ,
7. 2 Ibf-ft )
CONTRO L UNI TBRACKE T
TCM
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Road Tes t
NOTE : War m u p th e engin e to norma l operatin g temperatur e (th e radiato r fa n come s on) .
1. Appl y parkin g brak e an d bloc k th e wheels . Star t th e engine , the n shif t t o positio n whil e depressin g th e brak e
pedal . Depres s th e accelerato r peda l an d releas e it suddenly . Th e engine should no t stall .
2. Repea t sam e tes t i n position .
3. Shif t t o position , an d chec k tha t th e shif t point s o n a fla t roa d occu r a t th e approximat e speed s show n o n th e nex t
page . Als o chec k fo r abnorma l nois e an d clutc h slippage .
NOTE : Throttl e positio n senso r voltag e represent s th e throttl e opening .
-1 . Remov e th e TC M cove r t o expos e th e TC M fo r roa d testing ; refe r t o pag e 14-5 4 an d 14-55 .
-2 . Se t th e digita l multimete r t o chec k voltag e betwee n B 4 (+ ) termina l an d A1 3 (- ) o r A2 6 (- ) termina l o f th e TC M fo r
th e throttl e positio n sensor .
NOTE : Refe r t o pag e 14-55 ; Ho w to us e th e Backprob e Set .
SR S 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 .
BACKPROB EADAPTER
B4 Termina l
BACKPROB E SE T07SAZ-001000 A
(tw o required )
A13 o r A2 6Termina l
STACKING PATC H
CORD
TCM
DIGITA L MULTIMETE R
(Commerciall y available )
KS - AH M - 3 2 - 003 ,or equivalen t
TC M CONNECTOR S
WIR E SID E O F FEMAL E TERMINAL S
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