1995 ACURA TL fuse box

Idle Contro l Syste m
Brake Switc h Signa l
This signal s th e PC M whe n th e brak e peda l i s depressed .
Inspection o f Brak e Switc h Signal .
Ar e th e brak e light s o n withou t
depressin g th e brak e pedal ? Inspec
t th e brak e switc h (se e
sectio n 19 ).
Depres s th e brak e pedal .
D o th e brak e light s com e on ?
Is th e fus e OK ?
Chec k fo r a n ope n i n th e wir e
(BKS W line) :
1 . Depres s th e brak e pedal .
2 . Measur e voltag e betwee n PC M
connecto r terminal s E 2 an d
A2 6 wit h th e brak e peda l de -
pressed .
Repair shor t i n th e wire be-
twee n th e brak e switc h an d
th e STO P HOR N (2 0 A ) fuse .
Replac e th e STO P HOR N (2 0 A )
fuse .
Repai r ope n i n th e wir e be -
twee n th e brak e switc h an d
th e STO P HOR N (2 0 A ) fuse .
Inspec t th e brak e switc h (se e
sectio n 19 ).
A (26P )PCM CONNECTOR SE (26P)
Wire sid e o f femal e terminal s
I s ther e batter y voltage ? Repai
r ope n in th e wir e betwee n
th e PC M (E2 ) an d th e brak e switch .
Brak e switc h signa l i s OK . Inspec
t th e STO P HOR N (2 0 A )
fus e i n th e under-hoo d fuse / rela y
box.
ProCarManuals.com

Fuel Suppl y Syste m
Fuel Pressur e Regulato r (cont'd )
(From pag e 11-125 )
Chec k fo r a n ope n in th e wire :
Measur e voltag e betwee n th e
contro l bo x 4 P connecto r termi -
na l No . 4 an d bod y ground .
I s ther e batter y voltage ?
Chec k fo r a n ope n in th e wire :
1 . Tur n th e ignitio n switc h OFF .
2 . Reconnec t th e 4 P connecto r
t o th e contro l box .
3 . Star t th e engin e an d allo w it
to idle .4. Connec t PC M connecto r ter -
mina l A1 0 an d bod y groun d
with a jumpe r wire .
Is ther e manifol d vacuum ? CONTRO
L BO X
4 P CONNECTO R (C218 )
Repai r ope n i n wir e betwee n
No. 4 EC U (PCM ) (15 A ) o r (2 0 A )fus e in th e under-das h fuse/rela y
bo x an d th e 4 P connector . Wir
e sid e o f femal e terminal s
PC M CONNECTO R A (26P )
Wir e sid e o f femal e terminal s
Repai r ope n i n wir e betwee n
PC M (A10 ) an d th e 4 P connector .
Fue l Pressur e Regulato r Contro l
Solenoi d Valv e is OK .
JUMPE RWIRE
ProCarManuals.com

Fuel Suppl y Syste m
PGM-F I Mai n Rela y (cont'd )
Troubleshootin g Flowchar t
Engine wil l no t start .Inspectio n o f PGM-F I mai nrelay an d rela y harness .
Check fo r a n ope n in th e wir e (PG 1line) :1. Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e PGM-F I mai n
rela y 4 P connecto r an d 8 P
connector .3. Chec k fo r continuit y betwee n
th e PGM-F I mai n rela y 8 P
connecto r termina l No . 7 an d
bod y ground . PGM-F
I MAI N RELA Y 8P CONNECTO R (C417 )
Wir e sid e o f femal e terminal s
I s ther e continuity ? Repai
r ope n in th e wir e betwee n
th e PGM-F I mai n rela y an d G10 1
(locate d a t righ t middl e o f
engine) .
Check fo r a n ope n o r shor t i n th e
wir e (BA T line) :
Measur e voltag e betwee n th e
PGM-F I mai n rela y 4 P connecto r
termina l No . 3 an d bod y ground . PGM-F
I MAI N RELA Y 4P CONNECTO R (C418 )
BAT(YEL /BLU)
Wire sid e o f femal e terminal s
I s ther e batter y voltage ? Repai
r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e EC U (PCM )
(2 0 A ) fuse .
Replac e th e EC U (PCM ) (2 0 A )
fus e in th e under-hoo d fuse /
relay box .
Chec k fo r a n ope n o r shor t i n th e
wir e (IGS W line) :
1 . Tur n th e ignitio n switc h O N (II) .
2 . Measur e voltag e betwee n th e
PGM-F I mai n rela y 8 P connec -
to r termina l No . 5 an d bod y
ground .
Is ther e batter y voltage ?
(T o pag e 11-131 ) Repai
r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e No . 2 FUE L
PUM P (1 5 A ) fuse .
Replac e th e No . 2 FUE L PUM P
(15 A ) fus e i n th e under-das hfuse/relay box .
ProCarManuals.com

(From pag e 11-130 )
Chec k fo r a n ope n i n th e wir e
(IGS W line) :
Measur e voltag e betwee n th e
PGM-F I mai n rela y 4 P connecto r
termina l No . 4 an d bod y ground . PGM-F
I MAI N RELA Y 4 P CONNECTO R (C418 )
I s ther e batter y voltage ? Repai
r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e I G COI L
(3 0 A ) fuse .
Replac e th e IG 1 1 G COI L (3 0
A ) fus e i n th e ignitio n coi l
fus e holder . Wir
e sid e o f femal e terminal s
Chec k fo r a n ope n o r shor t i n th e
wir e (ST S line) :
1 . Tur n th e ignitio n switc h t o th e
STAR T (III ) positio n (Trans -
missio n i n [N ] o r [P] position) .
2 . Measur e th e voltag e betwee n
th e PGM-F I mai n rela y 8 P con -
necto r termina l No . 3 an d
body ground .
PGM-FI MAI N RELA Y 8 P CONNECTO R (C417 )
I s ther e batter y voltage ? Repai
r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e No . 9
STARTE R SIGNA L (7. 5 A ) fuse .
Replac e th e No . 9 STARTE R
SIGNA L (7. 5 A ) fus e i n th e
under-das h fuse/rela y box . Wir
e sid e o f femal e terminal s
Chec k fo r a n ope n i n th e wir e
(FLR 1 line) :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e PC M connec -tor A (2 6 P ) fro m th e PCM .3. Chec k fo r continuit y betwee n
th e PGM-F I mai n rela y 8 P
connecto r termina l No . 2 an d
PC M connecto r termina l A4 .
I s ther e continuity ?
(T o pag e 11-132 ) Repai
r ope n in th e wir e betwee n
th e PC M (A4 ) an d th e PGM-F I
mai n relay . PC
M CONNECTO R A (26P )
Wir e sid e o f femal e terminal s
ProCarManuals.com

Intake Air System

System Description

The system supplies air for all engine needs. It consists of the intake air pipe, Air Cleaner (ACL), intake air duct, Throttle

Body (TB), Idle Air Control (IAC) Valve, fast idle thermo valve, and intake manifold.

A resonator in the intake air pipe provides additional silencing as air is drawn into the system.

IAB LOW

CONTROL

SOLENOID

VALVE
IAB HIGH

CONTROL SOLENOID VALVE

IAB LOW

CONTROL

DIAPHRAGM

VALVE
From PGM-FI

MAIN RELAY

From No. 4 ECU

(PCM)
(15 A)

FUSE

(in the under-dash

fuse/relay box)

VARIOUS

SENSORS

INTAKE

AIR

DUCT

FAST

IDLE

THERMO

VALVE
IDLE

ADJUSTING

SCREW
ENGINE

COOLANT
INTAKE

MANIFOLD
PCM
IAB

VACUUM

TANK
IAB

CHECK

VALVE

IAB HIGH

CONTROL

DIAPHRAGM

VALVEProCarManuals.com

Intake Ai r Syste m
Intake Ai r Bypas s (IAB ) Contro l Syste m (cont'd )
(From pag e 11-139 )
Chec k fo r vacuu m at idle :
Remov e No . 8 vacuu m hos e fro m
th e IA B hig h contro l diaphrag m
valv e an d connec t a vacuu m gaug e
t o th e hose .
I s ther e vacuum ?
(T o pag e 11-141 ) (Fro
m pag e 11-139 )
I s ther e batter y voltage ?
Chec k fo r a n ope n i n th e wir e
(IABCS 1 line) :
1. Tur n th e ignitio n switc h OFF .2. Chec k fo r continuit y betwee nPCM connecto r termina l A2 0and 4 P connecto r termina lNo. 4 .
Is ther e continuity ?
Substitut e a known-goo d PC M
an d recheck . I f sympto m goe s
away , replac e th e origina l PCM .
Chec k fo r vacuu m at IA B vacuu m
tank :
Disconnec t th e No . 4 vacuu m
hos e o n IA B lo w contro l solenoi d
valv e an d connec t a vacuu m
gaug e t o th e hose .
I s ther e vacuum ?
Chec k fo r a n ope n i n th e wir e
(IABCS 2 line) :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e 4 P connecto r
fro m th e IA B contro l solenoi d
valv e assy .
3 . Star t engin e an d allo w i t t o
idle .4. Measur e voltag e betwee n 4 P
connecto r termina l No . 1 an d
No. 3 .
(T o pag e 11-141 ) Repai
r ope n in wir e betwee n th e
4 P connecto r an d No . 4 EC U
(PCM ) (1 5 A ) fus e i n th e under -
das h fuse/rela y box .
PC M CONNECTO R A (26P )
IAB CONTRO LSOLENOID VALV EASSY. 4 PCONNECTO R (C203 )
Wire sid e o f
femal e
terminal s
Repai r ope n i n wir e betwee n
PC M (A20 ) an d th e 4 P connector .
No . 8 VACUU M HOS E
IAB HIG H
CONTRO LDIAPHRAG MVALVE
VACUU M
PUMP/GAUG E
A973 X - 04 1 -
XXXX X
Repair th e blockag e o r vacuu m
lea k betwee n th e IA B vacuu m
tan k an d th e intak e manifold .
Wir e sid e o f femal e terminal s
ProCarManuals.com

(From pag e 11-140 ) (From pag e 11-140 )
I s ther e batter y voltage ?
Chec k fo r a n ope n in th e wir e (IG 1
line) :Measur e voltag e betwee n 4 P con -
necto r termina l No . 1 an d bod y
ground .
I s ther e batter y voltage ?
Chec k fo r a n ope n i n th e wire
(IABCS 2 line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Chec k fo r continuit y betwee n
PC M connecto r termina l A2 2
an d 4 P connecto r termina l
No. 3 .
Is ther e continuity ?
Chec k th e IA B Lo w Contro l Sole -
noi d Valve :
Disconnec t th e 4 P connecto r fro m
th e IA B contro l solenoi d valv e
assembly . Replac
e th e IA B hig h contro l
solenoi d valve .
IAB CONTRO L SOLENOI D VALV EASSY. 4 P CONNECTO R (C203 )
Wire sid e o f femal e
terminal s
Repai r ope n in wir e betwee n th e
4 P connecto r an d No . 4 EC U
(PCM ) (1 5 A ) o r (20A ) fus e in th e
under-das h fuse/rela y box .
PC M CONNECTO R A (26P )
Repai r ope n i n wir e betwee n
PC M (A22 ) an d th e 4 P connector .
I s ther e vacuum ? Replac
e th e IA B lo w contro l sole -
noi d valve .
(T o pag e 11-142 ) (To pag e 11-142 )
Substitut e a known-goo d PC Mand recheck . I f sympto m goe s
away , replac e th e origina l PCM .
I s ther e vacuum ?
Chec
k fo r vacuu m at 3,40 0 rpm :
1 . Rais e engin e spee d t o 3,40 0
rpm.2. Chec k fo r vacuu m a t No . 2
vacuu m hose .
ProCarManuals.com

Emission Control System

Exhaust Gas Recirculation (EGR) System

Description

The EGR system is designed to reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the EGR

valve and the intake manifold into the combustion chambers. It is composed of the EGR valve, EGR vacuum control valve,

EGR control solenoid valve, PCM and various sensors.

The PCM contains memories for ideal EGR valve lifts for varying operating conditions. The EGR valve lift sensor detects

the amount of EGR valve lift and sends the information to the PCM. The PCM then compares it with the ideal EGR valve lift

which is determined by signals sent from the other sensors. If there is any difference between the two, the PCM cuts cur-

rent to the EGR control solenoid valve to reduce vacuum applied to the EGR valve.

EGR VALVE

LIFT SENSOR
INTAKE

MANIFOLD

From No. 4 ECU (PCM)

FUSE (15 A) or (20 A)

(in the under-dash

fuse/relay box)

EGR

CONTROL

SOLENOID

VALVE

EGR

VACUUM

CONTROL

VALVE
VARIOUS

SENSORS
EGR VALVEProCarManuals.com