radiator ACURA TL 1995 Service User Guide

Radiator
Replacemen t
1. Drai n engin e coolant .
2 . Remov e th e uppe r an d lowe r radiato r hoses , an d
AT F coole r hoses .
3 . Disconnec t th e fa n moto r connector s an d EC T
switc h A connector .
4 . Remov e th e radiato r uppe r brackets , the n pul l u p
th e radiator . 5
. Remov e th e fa n shrou d assemblie s an d othe r part s
from th e radiator .
Install th e radiato r i n th e revers e orde r o f removal :
NOTE:
• Se t th e uppe r an d lowe r cushion s securely .
• Fil l th e radiato r wit h engin e coolan t an d blee d
the air .
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m ,
7. 2 Ibf-ft )UPPE R BRACKE TAND CUSHIO N
RADIATO R
ATF COOLE R
HOS E
Refe r t o sectio n 1 4
whe n installing .
LOWERRADIATO RHOSE
RADIATO R FA N SWITC H A
2 4 N- m (2. 4 kgf-m ,
1 7 Ibf-ft )
COOLAN T
RESERVOI R
6 x 1. 0 m m7 N- m (0. 7 kgf-m ,
5 Ibf-ft )
RADIATO R FA N
SHROU D
CONDENSO R
FA N SHROU D
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m , 7. 2 Ibf-ft )
LOWE RCUSHIO N
FAN MOTO R
CONNECTO R
EC T SWITC H A
CONNECTO R
O-RIN
G
Replace .
DRAIN
PLU G
O-RIN G
Replace .
UPPERRADIATO RHOSE
RADIATO RCAP
ProCarManuals.com

Radiator
Cap Testin g
1. Remov e th e radiato r cap , we t it s sea l wit h engin e
coolant , the n instal l i t o n th e pressur e tester .
2 . Appl y a pressur e o f 9 3 - 12 3 kP a (0.9 5 - 1.2 5 kgf/cm
2,
14-1 8 psi) .
3. Chec k fo r a dro p in pressure .
4 . I f th e pressur e drops , replac e th e cap .
RADIATO R PRESSUR E TESTE R
(Commerciall y available )
RADIATO R
CAP
ADAPTO R
(fo r 3 2 m m neck , lo w profile )
Testing
1. Wai t unti l th e engin e i s cool , the n carefull y remov e
the radiato r ca p an d fil l th e radiato r wit h engin e
coolan t t o th e to p o f th e fille r neck .
2 . Attac h th e pressur e teste r t o th e radiato r an d appl y
a pressur e o f 93-12 3 kP a (0.9 5 - 1.2 5 kgf/cm
2, 1 4 -
18 psi) .
3. Inspec t fo r engin e coolan t leak s an d a dro p i n pres -
sure.
4. Remov e th e teste r an d reinstal l th e radiato r cap .
NOTE : Chec k fo r engin e oi l i n th e coolan t and/o r
coolan t i n th e engine oil.
RADIATO R PRESSUR ETESTER(Commerciall y available )
ADAPTO R
(for 3 2 m m neck , lo w profile )
ProCarManuals.com

Thermostat Radiato
r Fa n Switche s
Testing
Replac e th e thermosta t i f i t i s ope n a t roo m temperature .
T o tes t a close d thermostat :
1 . Suspen d th e thermosta t i n a containe r o f wate r a s
shown .
2 . Hea t th e water , an d chec k th e temperatur e wit h a
thermometer . Chec k th e temperatur e a t whic h th e
thermosta t firs t opens , an d a t whic h i t i s full y open .
CAUTION : D o no t le t th e thermomete r touc h th e
botto m of th e ho t container .
3 . Measur e lif t heigh t of the thermosta t whe n full y
open .
STANDAR D THERMOSTA T
Lift height :
Primar y valve : 10. 0 m m (0.3 9 in ) min .
Secondar y valve : 8. 5 m m (0.3 3 in ) min .
Start s opening :
Primar y valve : 176-183° F (80-84°C )
Secondar y valve : 18 1 - 189° F (8 3 - 87°C )
Full y open : 203° F (95°C )
THERMOMETE R
THERMOSTA T
Testing
Removin g th e radiato r fa n switc h whil e
th e engin e is ho t ca n caus e th e coolan t t o spra y out , seri -
ousl y scaldin g you . Alway s le t th e engin e an d radiato r
coo l dow n befor e removin g th e switch .
NOTE : Blee d ai r fro m th e coolin g syste m afte r installin g
th e radiato r fa n switc h (se e pag e 10-5 ).
1 . Remov e th e radiato r fa n switc h A fro m th e radiato r
(se e pag e 10-2 ) an d radiato r fa n switc h B fro m th e
thermosta t housin g (se e pag e 10-9 ).
2 . Suspen d th e switc h i n a containe r of wate r a s
shown .
THERMOMETE R
RADIATORFANSWITC H
WATER
3. Hea t th e wate r an d chec k th e temperatur e wit h a
thermometer .
CAUTION : D o no t le t th e thermomete r touc h th e
botto m of th e ho t container .
4 . Measur e th e resistanc e betwee n th e A an d B termi -
nal s accordin g t o th e table .
ProCarManuals.com

PGM-FI System

System Description

INPUTS
ENGINE CONTROL MODULE (ECM)

OUTPUTS

Fuel Injectors

PGM-FI Main Relay (Fuel Pump)

MIL

IAC Valve

A/C Compressor Clutch Relay

Radiator Fan Relay

Condenser Fan Relay

ALT

ICM

EVAP Purge Control Solenoid

Valve

Primary HO2S Heater

Secondary H02S Heater

EGR Control Solenoid Valve

IAB Control Solenoid Valve

EVAP Bypass Solenoid Valve*2

EVAP Control Canister Vent Shut

Valve*2

*1: '95-96 models

*2: '97 - 98 models

PGM-FI System

The PGM-FI system on this model is a sequential multiport fuel injection system.

Fuel injector Timing and Duration

The ECM contains memories for the basic discharge durations at various engine speeds and manifold air flow rates. The

basic discharge duration, after being read out from the memory, is further modified by signals sent from various sensors

to obtain the final discharge duration.

Idle Air Control

Idle Air Control Valve (IAC Valve)

When the engine is cold, the A/C compressor is on, the transmission is in gear, the brake pedal is depressed, the P/S load

is high, or the alternator is charging, the ECM controls current to the IAC Valve to maintain the correct idle speed.

Ignition Timing Control

• The ECM contains memories for basic ignition timing at various engine speeds and manifold air flow rates. Ignition

timing is also adjusted for engine coolant temperature.

• A knock control system is also used. When detonation is detected by a knock sensor (KS), the ignition timing is retarded.

Other Control Functions

1. Starting Control

When the engine is started, the ECM provides a rich mixture by increasing fuel injector duration.

2. Fuel Pump Control

• When the ignition switch is initially turned on, the ECM supplies ground to the PGM-FI main relay that supplies

current to the fuel pump for two seconds to pressurize the fuel system.

• When the engine is running, the ECM supplies ground to the PGM-FI main relay that supplies current to the fuel pump.

• When the engine is not running and the ignition is on, the ECM cuts ground to the PGM-FI main relay which cuts

current to the fuel pump.

3. Fuel Cut-off Control

• During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at

speeds over 1,250 rpm.

• Fuel cut-off action also takes place when engine speed exceeds 7,100 rpm, regardless of the position of the throttle

valve, to protect the engine from over-revving.
CKP/TDC/CYP Sensor

CKF Sensor

MAF Sensor

ECT Sensor

IAT Sensor

TP Sensor

EGR Valve Lift Sensor

Primary HO2S

Secondary H02S

VSS

BARO Sensor

ELD

Front KS

Rear KS

Starter Signal

ALT FR Signal

Air Conditioning Signal

A/T Gear Position Signal

Battery Voltage (IGN.1)

Brake Switch Signal

PSP Switch Signal

EVAP Purge Flow Switch*1

Fuel Tank Pressure Sensor*2ProCarManuals.com

Throttle Cable

Inspection/Adjustment

1.

2.

3.
Start the engine. Hold the engine at 3,000 rpm with

no load (transmission in or position) until the

radiator fan comes on, then let it idle.

Check that the throttle cable operates smoothly with

no binding or sticking. Repair as necessary.

Check cable free play at the throttle linkage. Cable

deflection should be 10 - 12 mm (0.39 - 0.47 in.)

CABLE

BRACKET.
ADJUSTING

NUT

LOCKNUT

DEFLECTION

10-12
mm

(0.39
-
0.47 in.)

4. If deflection is not within specs, loosen the locknut,

turn the adjusting nut until the deflection is as spec-

ified, then retighten the locknut.

5. With the cable properly adjusted, check the throttle

valve to be sure it opens fully when you push the

accelerator pedal to the floor. Also check the throttle

valve to be sure it returns to the idle position whenev-

er you release the accelerator pedal.
Installation

1. Fully open the throttle valve, then install the throttle

cable in the throttle linkage and install the cable

housing in the cable bracket.

CABLE

BRACKET

THROTTLE

LINKAGE
ADJUSTING

NUT

LOCKNUT

INNER CABLE

2. Start the engine. Hold the engine at 3,000 rpm with

no load (transmission in or position) until the

radiator fan comes on, then let it idle.

3. Hold the cable sheath, removing all slack from the

cable.

4. Turn the adjusting nut until it is 3 mm (0.12 in.) away

from the cable bracket.

CABLE

BRACKET

ADJUSTING NUT

LOCKNUT

9.8 N-m

(1.0 kgf-m,

7.2 Ibf-ft)
3 mm

(0.12 in.)

5.
Tighten the locknut. The cable deflection should now

be 10 - 12 mm (0.39 - 0.47 in.). If not, see inspection/

adjustment.ProCarManuals.com

ATF Cooler Hoses

Connection

1. Connect the ATF hoses to the lines, and secure them with the clips as shown.

2. Install the lower hose on lower cutout of the clamp and install upper hose on upper part of the clamp.

NOTE: When replacing the lower hose on the transmission, install the short side from the protector tube to the trans-

mission ATF cooler line.

TRANSMISSION
CLIP

RADIATOR
PIPE

6-8 mm

(0.24-0.31 in)

CLAMP

UPPER HOSE

LOWER

HOSE
PROTECTOR

TUBE

2-4 mm

(0.08-0.16 in)
ATF HOSE

6-8 mm

(0.24-0.31 in)ProCarManuals.com

Troubleshooting
Symptom Char t
For electrica l malfunction s whic h ar e indicate d b y th e self-diagnosti c system , refe r t o self-diagnosi s functio n (se e nex t
page) .
NOTE :
Check th e engin e coolan t level , an d allo w th e engin e t o war m u p befor e troubleshooting .
An y abnormalit y mus t b e correcte d befor e continuin g th e test .
Becaus e o f th e precis e measurement s needed , us e a multimete r whe n testing .
Befor e performin g an y troubleshootin g procedure s check :
— Fuse s * ' No . 1 7 (3 0 A) , *
1 No . 3 4 (2 0 A) , *1 No . 3 8 (2 0 A) , *1 No . 3 9 (1 0 A) , *2 No . 4 (*3), *2 No . 7 (7. 5 A) , *2 No . 8 (7. 5 A )
— Ground s No . G101 , G301 , G401 , G403 , G40 4
— Cleanlines s an d tightnes s o f al l connector s
*' : I n th e under-hoo d fuse/rela y bo x
*
2: I n th e under-das h fuse/rela y bo x
*3: No. 4 (1 5 A) : '9 5 an d '9 6 model s
: No. 4 (2 0 A) : '9 7 an d '9 8 model s
Sympto m
Check th e malfunctio n indicato r lam p (MIL) .
N o heate r an d A/ C in eithe r manual or AUT O modes .
Mod e contro l moto r doe s no t run , o r on e o r mor e mode s
are inoperative .
Recirculatio n contro l door s d o no t chang e betwee n FRES H
and RECIRCULATE .
Radiator fa n doe s no t ru n a t al l (bu t condense r fa n run s
with th e A/ C on) .
Condense r fa n doe s no t ru n a t al l (bu t radiato r fa n run s
with th e A/ C on) .
Both fan s (radiato r an d condenser ) d o no t ru n fo r engin e
cooling , bu t the y bot h ru n wit h th e A/ C on .
Bot h fan s d o no t ru n wit h th e A/ C on (2.5L) or at all (3.2L) .
Compresso r clutc h doe s no t engage .
A/ C syste m doe s no t com e o n (compresso r an d bot h fans) . Remed
y
Perfor m th e procedure s in th e flowchar t (se e pag e 22-28 ).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-29 ).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-30 ).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-32 ).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-34 , 2.5L) .
Perfor m th e procedure s i n th e flowchar t (se e pag e 22-37, 2.5L).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-40 ).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-41 , 2.5L) ( 22-18a, 3.2L).
Perfor m th e procedure s in th e flowchar t (se e pag e 22-43 ).
Perfor m th e procedure s i n th e flowchar t (se e pag e 22-46, 2.5L) (22-16a , 3.2L).
(see page 22-10a, 3.2L)
(see page 22-13a , 3.2L)
ProCarManuals.com

Troubleshooting

Radiator Fan Control Module Input Tests

NOTE: Perform the following tests with the radiator fan control module 8P connector connected, the ignition switch ON (II),

and the A/C switch OFF. If you find the cause of a problem, correct it before you continue.

RADIATOR FAN CONTROL MODULE 8P CONNECTOR

WIRE SIDE OF FEMALE TERMINALS

Terminal

No.

4

6

7

2

3

1

8

5
Wire

color

BLK

WHT/GRN

BLK/YEL

YEL/BLK

YEL/WHT

YEL

LT

GRN/YEL

WHT/GRN
Test condition

Check for voltage to body

ground.

Check for battery voltage:

Check for battery voltage:

Ignition switch - ON (II)

Check for battery voltage:

Ignition switch - ON (II)

Check for battery voltage:

Ignition switch - ON (II)

Check for battery voltage:

Ignition switch - ON (II)

Connect to body ground:

Ignition switch - ON (II)

Check for voltage.
Desired results

There should be less

than one volt.

There should be battery

voltage.

Condenser fan and radia-

tor fan should come on.

Approx. 11 V (engine

coolant temperature

below 207°F [97°C])
Corrective action if desired results are

not obtained

Repair open to body ground.

Check No. 39 (10 A) fuse in the under-

hood fuse/relay box; if OK, repair open

in the WHT/GRN wire.

Check No. 4* fuse in the under-dash

fuse/relay box; if OK, repair open in the

BLK/YEL wire.

Check No. 8 (7.5 A) fuse in the under-

dash fuse/relay box; if OK, repair open in

the YEL/BLK wire.

Replace the radiator fan control module.

Before you connect the new radiator fan

control module, disconnect both fan

relays. Check for continuity between the

YEL/WHT (or YEL) wire and ground, using

the 20 k scale on your ohmmeter. There

should be no continuity. If there is conti-

nuity, the new radiator fan control mod-

ule will be damaged when you connect it.

Check for an open in the LT GRN/YEL

wire between the radiator fan control

module and the condenser fan relay or

the radiator fan relay. If OK, check for an

open in the YEL/WHT wire between the

radiator fan control module and the con-

denser fan relay, or the YEL wire between

the radiator fan control module and the

radiator fan relay. If OK, test the con-

denser fan relay or the radiator fan relay.

Faulty engine coolant temperature (ECT)

switch B, short to body ground, or faulty

radiator fan control module.

* No.4 (15 A): '95 and '96 models

No.4 (20 A): '97 and '98 modelsProCarManuals.com

Condenser
Replacemen t
1. Recove r th e refrigeran t wit h a Recovery/Recycling /
Charging Syste m (se e pag e 22-71 ).
2 . Remov e th e fron t grill e (se e sectio n 20 ).
3 . Remov e th e bolt , th e reservoi r hos e bracke t an d th e
coolan t reservoir .
NOTE : D o no t disconnec t th e reservoi r hos e fro m
th e coolan t reservoi r an d th e radiator .
COOLAN T RESERVOI R
BRACKET
4. Remov e th e powe r steerin g clam p an d th e wir e har -
nes s cli p fro m th e condense r fa n shroud .
Disconnec t th e condense r fa n connector . Loose n
th e tw o lowe r mountin g bolts , the n remov e th e tw o
uppe r mountin g bolt s an d th e condense r fa n
shroud .
NOTE : B e carefu l no t t o damag e th e radiato r fin s
whe n removin g th e condense r fa n shroud .
6 x 1. 0 m m8 N- m (0. 8 kgf-m , 6 Ibf-ft )
WIR E HARNES S
CLIPS
6 x 1. 0 m m8 N- m(0.8 kgf-m ,
6 Ibf-ft )
CLAM P
WIR E HARNES S
CLIP S CONDENSE
R FA N
SHROU D
CONDENSE R FA N
CONNECTO R
6 x 1. 0 m m8 N- m (0. 8 kgf-m , 6 Ibf-ft )
5. Remov e th e condense r fa n rela y fro m th e
receiver/drye r bracket . Disconnec t th e receive r lin e
fro m th e receiver/drye r an d th e condense r lin e fro m
th e condenser , the n remov e th e tw o bolt s an d th e
receiver/dryer . Disconnec t th e discharg e lin e fro m
th e condenser .
NOTE : Plu g o r ca p th e line s immediatel y afte r dis -
connectin g the m to avoi d moistur e an d dus t con -
tamination .
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m , 7. 2 Ibf-ft )
RECEIVER /DRYER
13 N- m(1.3 kgf-m ,
9. 4 Ibf-ft )
RECEIVE RLINE
CONDENSE R LIN E
CONDENSE R
FA N RELA Y
2 2 N- m (2. 2 kgf-m , 1 6 Ibf-ft )
DISCHARG E LIN E
6. Remov e th e fou r bolt s an d th e tw o radiato r uppe r
moun t brackets .
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m , 7. 2 Ibf-ft )
UPPE R MOUN T
BRACKET S
ProCarManuals.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