engine ACURA TL 1995 Service Repair Manual

Troubleshooting

Tips and Precautions

Before Troubleshooting

Check applicable fuses in the appropriate fuse/relay

box.

Check the battery for damage, state of charge, and

clean and tight connections.

Check the alternator belt tension.

CAUTION:

Do not quick-charge a battery unless the battery

ground cable has been disconnected, otherwise you

will damage the alternator diodes.

Do not attempt to crank the engine with the battery

ground cable loosely connected or you will severely

damage the wiring.

Handling Connectors

Make sure the connectors are clean and have no loose

wire terminals.

Make sure multiple cavity connectors are packed with

grease (except waterproof connectors).

All connectors have push-down release type locks.

LOCKING TAB

Some connectors have a clip on their side used to

attach them to a mount bracket on the body or on

another component. This clip has a pull type lock.

Some mounted connectors cannot be disconnected

unless you first release the lock and remove the con-

nector from its mount bracket.

LOCKING

PAWL ON

OTHER

HALF OF

CONNECTOR
Pull to

disengage

BRACKET
Never try to disconnect connectors by pulling on

their wires; pull on the connector halves instead.

Always reinstall plastic covers.

Before connecting connectors, make sure the termi-

nals are in place and not bent.

BENT TERMINAL

Check for loose retainer and rubber seals.

RETAINER
RUBBER SEAL RETAINER

The backs of some connectors are packed with

grease. Add grease if necessary. If the grease is con-

taminated, replace it.
LOCKING TABProCarManuals.com

Relay and Control Unit Locations

Engine Compartment

UNDER-HOOD ABS

FUSE/RELAY BOX

ABS PUMP MOTOR RELAY

HEADLIGHT

RELAY
DIMMER RELAY
TAILLIGHT

RELAY
POWER WINDOW

RELAY
UNDER-HOOD

FUSE/RELAY BOXProCarManuals.com

Relay and Control Unit Locations

Engine Compartment (cont'd)

INTERMITTENT WIPER

RELAY

Wire colors: BLU/YEL, GRN/YEL,

BLK, GRN/BLK and BLU/WHT

A/C COMPRESSOR CLUTCH RELAY

Wire colors: RED/BLU, RED,

YEL/BLK and WHT

CONDENSER FAN RELAY

Wire colors: LT GRN/YEL,

WHT/GRN, YEL/WHT and WHT

RADIATOR FAN RELAY

Wire colors: LT GRN/YEL,

WHT/BLU, YEL and WHTProCarManuals.com

Starting Syste m
Starter Tes t
NOTE : Th e ai r temperatur e mus t b e betwee n 5 9 an d
100° F (1 5 an d 38°C ) befor e testing .
Recommende d Procedure :
Use a starte r syste m tester .
Connec t an d operat e th e equipmen t i n accordanc e
wit h th e manufacturer' s instructions .
Tes t an d troubleshoo t a s described .
Alternate Procedure :
Use followin g equipment :
— Ammeter , 0 - 400 A
— Voltmeter , 0 - 20 V (accurat e withi n 0. 1 volt )
— Tachometer , 0 - 1,20 0 rp m
Hoo k u p a voltmete r an d ammete r a s shown .
NEGATIV ETERMINA L
NOTE: Afte r thi s test , o r an y subsequen t repair , rese t
th e EC M to clea r an y code s (se e sectio n 11 ).
Chec k th e Starte r Engagemen t
1 . Disconnec t th e 4 P connecto r fro m th e ignitio n coil .
IGNITIO N COI L
4P CONNECTO R
2. Wit h th e shif t leve r i n o r , turn th e ignitio n
switch to STAR T (III) .
Th e starte r shoul d cran k th e engine . I f th e starte r
doe s no t cran k th e engine , g o to ste p 3 .
I f i t crank s th e engin e erraticall y o r to o slowly , g o
t o "Chec k fo r Wea r an d Damage " o n th e nex t
page .
3. Chec k th e battery , batter y positiv e cable , ground ,
starte r cu t relay , securit y contro l unit , an d th e wir e
connection s fo r loosenes s an d corrosion . Tes t again . I f
th e starte r stil l doe s no t cran k th e engine , g o to ste p 4 .
4 . Unplu g th e connecto r (BLK/WH T wir e an d solenoi d
terminal ) fro m th e starter . Mak e sur e th e shif t leve r
is i n o r , then connec t a jumpe r wir e fro m th e
batter y positiv e (+ ) termina l t o th e solenoi d termi -
nal . Th e starte r shoul d cran k th e engine .
I f th e starte r stil l doe s no t cran k th e engine , remov e
it , an d diagnos e it s interna l problem .
I f th e starte r crank s th e engine , g o t o ste p 5 an d
continu e th e test .
5 . Chec k th e ignitio n switc h (se e pag e 23-66 ).
6 . Chec k th e starte r cu t rela y (se e pag e 23-63 ).
7 . Chec k th e A/ T gea r positio n switc h (se e pag e 23-146 ).
8 . Chec k th e securit y contro l uni t (se e pag e 23-283 ).
9 . Chec k fo r a n ope n in th e BLK/GR N wir e betwee n th e
ignitio n switc h an d starte r cu t relay , an d chec k fo r
a n ope n i n th e BLK/WH T wir e betwee n th e starte r
cu t rela y an d starter .
SOLENOI DTERMINA LWIRE
BLK/WH TWIRE
S (SOLENOID ) TERMINA L
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Check for Wear and Damage

The starter should crank the engine smoothly and steadily.

If the starter engages, but cranks the engine erratically,

remove it, and inspect the starter drive gear and torque

converter ring gear for damage.

Check the drive gear overrunning clutch for binding or

slipping when the armature is rotated with the drive

gear held. If the clutch is damaged, replace the clutch

assembly.

Check Cranking Voltage and Current Draw

Cranking voltage should be no less than 8.5 volts.

Current draw should be no more than 380 amperes.

If cranking voltage is too low, or current draw too high,

check for:

Dead or low battery

Open circuit in starter armature commutator segments

Starter armature dragging

Shorted armature winding

Excessive drag in engine

Check Cranking rpm

Engine speed during cranking should be above 100 rpm.

If speed is too low, check for:

Loose battery or starter terminals

Excessively worn starter brushes

Open circuit in commutator segments

Dirty or damaged helical spline or drive gear

Defective drive gear overrunning clutch

Check Starter Disengagement

With the shift lever in turn the ignition switch to

"START (III)", and release to "ON (II)". The starter drive

gear should disengage from the drive plate/ring gear

when you release the key.

If the drive gear hangs up on the drive plate/ring gear,

check for:

• Solenoid plunger and switch malfunction

• Dirty drive gear assembly or damaged overrunning

clutchProCarManuals.com

Ignition Syste m
Descriptio n
Ignition Timin g Control :
Th e programme d ignitio n (PGM-IG ) 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 intak e ai r flo w mass . Th e inpu t signal s ar e transmitte d b y th e
TDC/CKP/CY P sensor , throttl e positio n (TP ) sensor , engine coolant temperatur e (ECT ) sensor , an d MA F sensor . Thi s sys -
tem , whic h i s 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 char -
acteristic s whic h canno t b e provide d b y conventiona l governor s o r diaphragms .
Basi c Control :
The contro l uni t ha s store d withi n it th e optimu m basi c ignitio n timin g fo r operatin g condition s base d upo n engin e spee d
and intak e ai r flo w mass . Wit h compensatin g signal s fro m sensors , th e syste m determine s optimu m ignitio n timin g an d
duratio n fo r ambien t condition s an d send s voltag e pulse s t o th e ICM .
Compensatio n of ignitio n timing :
Compensatio n Ite m
Idlin g
Compensatio n a t warm-u p
ECT compensatio n Relate
d Senso r an d Informatio n
TDC/CKP/CY P senso r
MAF senso r
ECT senso r
ECT senso r
Descriptio n
Ignition 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 is 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
operating performanc e an d exhaus t ga s level .
Compensatio n fo r lea d angl e a t lo w engin e
coolan t temperatur e an d la g angl e a t hig h engin e
coolan t temperature .
Control a t Start :
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 TD C senso r (crankin g rpm ) an d starte r signal .
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Ignition Syste m
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.
2 .
Star t th e engine . Hol d th e engine at 3,00 0 rp m wit h
no loa d (shif t leve r i n o r position ) unti l th e
radiato r fa n come s on , the n le t i t idle .
Pul l ou t th e servic e chec k connecto r locate d unde r
th e glov e box . Connec t th e GRN/BL U an d OR N wir e
terminal s wit h th e specia l tool .
SCS SERVIC E CONNECTO R
( 07PAZ-0010100 )
SERVIC E CHEC K CONNECTO R (2P)
NOTE : Locate d unde r th e glov e bo x
3. Chec k th e idl e spee d (se e pag e 23-85 ).
4 . Connec t a timin g ligh t t o th e No . 1 ignitio n wire .
Poin t th e ligh t towar d th e pointe r o n th e timin g
bel t cover .
NO. 1 PLU G WIR E
TIMIN G LIGH T
5. Inspec t ignitio n timin g a t idl e speed .
Ignitio n Timing :
15 ° ± 2° BTD C (RED ) a t 70 0 ± 50 rp m wit h shif t leve r
in o r positio n an d electrica l system s turne d
off.
POINTE R
RE D MAR K
CRANKSHAFT
PULLEY
6. I f th e ignitio n timin g i s incorrect , replac e th e EC M
(ther e is n o wa y t o adjus t ignitio n timing) .
7 . Disconnec t th e specia l too l fro m th e servic e chec k
connector .
WHITE MAR K(TDC)
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Idle Spee d Chec k
1. Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (shif t leve r i n o r ) 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 connec -
tor.
TES T TACHOMETE R CONNECTO R
TES T TACHOMETE R CONNECTO R
BATTERY
Idle speed : 70 0 ± 5 0 rp m wit h shif t leve r i n positio n
or an d electrica l system s turne d off .
3 . Adjus t th e idl e spee d if necessar y (se e sectio n 11 ).
Distributo r Remova l
1. Disconnec t th e ignitio n wire s fro m th e distributo r
ignition (Dl ) cap .
MOUNTIN GBOLTS
2. Remov e th e distributo r mountin g bolts , the n remov e
th e distributo r fro m th e cylinde r head .
CLIP
TACHOMETE R
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Distributor Top End Inspection

1. Check for rough or pitted rotor and cap terminals.

2. Scrape or file off the carbon deposits. Smooth the

rotor terminal with an oil stone or #600 sandpaper if

rough.

ROTOR

TERMINAL
CAP TERMINAL

CARBON

POINT

3. Check the distributor ignition (Dl) cap for cracks, wear,

and damage. If necessary, clean or replace it.
Noise Condenser Capacity Test

1. Use a commercially available condenser tester.

Connect the condenser tester probes and measure

the condenser capacity.

Condenser capacity: 0.47 ± 0.09 microfarads

POSITIVE TERMINAL

BODY GROUND

(Negative)

NOTE: The noise condenser is intended to reduce

ignition noise. However, condenser failure may cause

the engine to stop running.

2. If not within the specifications, replace the noise con-

denser.ProCarManuals.com

Charging System

Description

To improve fuel economy, the alternator control system within the ECM changes the voltage generated at the alternator in

accordance with driving conditions.

Throttle position (TP) sensor

Engine coolant temperature

(ECT) sensor

Intake air temperature (IAT)

sensor

TDC/CKP/CYP sensor

Vehicle speed sensor (VSS)

ELD

Air conditioning signal
ECM

Alternator

STARTER SWITCH ON
Generated voltage decreases from 14.0 V to 12.5 V

AND

ELECTRICAL LOAD below 15 A

and

VEHICLE SPEED between 9 mph (15 km/h) and

44 mph (70
km/h)

and

ENGINE SPEED between 1,100 rpm and 3,000 rpm

and

ENGINE COOLANT TEMPERATURE above 176°F

(80°C)

and

A/C SWITCH OFF

and

INTAKE AIR TEMPERATURE above 65°F (18°C)
AND

FUEL CUT-OFF CON-

TROL function is not

engaged.ProCarManuals.com