1991 LEXUS SC300 oil

17
1. NORMALLYOPENOpens and
closes circuits,
thereby
stopping (1) or
allowing (2)
current flow.
RESISTOR An electrical component with a
fixed resistance, placed in a circuit
to reduce voltage to a specific
value.
RESISTOR, TAPPED A resistor which supplies two or
more different non±adjustable
resistance values.
SENSOR (Thermistor) A resistor which varies its
resistance with temperature.
SHORT PIN Used to provide an unbroken
connection within a junction block.
SOLENOID An electromagnetic coil which
forms a magnetic field when
current flows, to move a plunger,
etc. SWITCH, DOUBLE THROW
A switch which continuously
passes current through one set
of contacts or the other.
SWITCH,
IGNITION A key operated switch with
several positions which allows
various circuits, particularly the
primary ignition circuit, to
become operational.
Wires are always
drawn as straight lines
on wiring diagrams.
Crossed wires (1)
without a black dot at
the junction are not
joined; crossed wires
(2) with a black dot or
octagonal (
) mark at
the junction are spliced
(joined) connections.
RELAY, DOUBLE THROW
A relay which passes current
through one set of contacts or the
other.
SENSOR, ANALOG SPEED Uses magnetic impulses to open
and close a switch to create a
signal for activation of other
components. TRANSISTOR
A solidstate device typically used
as an electronic relay; stops or
passes current depending on the
voltage applied at ªbase.º
SWITCH, WIPER PARK
Automatically returns wipers to
the stop position when the wiper
switch is turned off.
SWITCH, MANUAL SPEAKER
An electromechanical device
which creates sound waves from
current flow.
2. NORMALLY CLOSED
RESISTOR, VARIABLE OR
RHEOSTAT A controllable resistor with a
variable rate of resistance.
Also called a potentiometer or
rheostat.
2. NORMALLY
OPEN
RELAY
1. NORMALLY
CLOSED Basically, an electrically
operated switch which may
be normally closed (1) or
open (2).
Current flow through a
small coil creates a
magnetic field which either
opens or closes an
attached switch.
(2) SPLICEDWIRES
(1) NOT CONNECTED
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236
GROUND POINT
FRONT TURN SIGNAL
LIGHT LH
ENGINE HOOD
COURTESY SW
TRACTION PUMP AND
MOTOR
HEATER RELAY
ABS ACTUATOR RELAY
TELEPHONE
TRANSCEIVER
AND SPEAKER RELAY
ENGINE OIL LEVEL
WARNING SW
COMBINATION METER
(E1 )
EFI ECU
TRACTION ECU
CHECK CONNECTOR
(
E1 ) CORNERING LIGHT LH
FRONT SIDE MAKER
LIGHT LH
BRAKE FLUID LEVEL
SW
FRONT CLEARANCE
LIGHT LH
FRONT SIDE MAKER
LIGHT RH
FRONT CLEARANCE
LIGHT RH
ABS ACTUATOR
FRONT TURN SIGNAL
LIGHT RH
CRUISE CONTROL
ACTUATOR
OXYGEN SENSOR SUB
(
FOR USA SPEC. )
TDCL (
E1 )
WASHER LEVEL SW EFI MAIN RELAY
CORNERING LIGHT RH
A/C PRESSURE SW
(HI GH PRESSURE )
AIR FLOW METER POWER STERRI NG
PRESSURE SW
NOISE FI LTER
(
FOR IGNI TION SYSTEM ) E4
E10
E12 2
2
BS1 4 E4
E7
E1 E5
EB EA I23
I33
E1 6
I32
E20
E20
E20
IK2 24
ED EC IK1
1 BY1
5
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W± B W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B BR
BR
W±B BR
BR
BR
W±B BR
BR±B BR BR
BR
BR
W± B
W± B
W± B
W± B
W± B
W± B
W± B
W±B
W±B
BR
BR
BR
BR BR
BR
BR
W±B
BR BR
BR
( EO1 )
( E11 )
( E1 )
( EO2 )
I27BR
(
S1 )
( E1 )
NOISE FILTER (
FOR
IGNITION SYSTEM )W±B
W/ TRACTION SYSTEM
NOI SE FILTER
(
FOR DEFOGGER SYSTEM )
W±B
W±B
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238
GROUND POINT
RADIO AND PLAYER
WOOFER SPEAKER
AMP LIFIER
STEREO POWER
AMP LIFIER
CHOKE COIL
HIGH MOUNT STOP
LIGHT
HIGH MOUNT STOP
LIGHT
FUEL LID OPENER
SOLENOID
WIRELESS DOOR LOCK
ECU
POWER SEAT CONTROL
SW(
FOR PASSENGER' S
SEAT )
POWER SEAT ECU
( FOR PASSENGER' S
SEAT )
SEAT HEATER RH
( FOR PASSENGER' S
SEAT BACK )
PPS ECU
REMOTE CONTROL
MIRROR ECU I31
II
BV2
8
IQ2
12
B23 : PIONEER
B24 : NAKAMICHI
BR
BR
BR BR
(
W/O CD PLAYER )
( W/ CD PLAYER ) BR
BR
A/C POWER
TRANSISTOR
BLOWER RESISTOR
(
FOR LOW SPEED )
ABS ECU
ABS AND
TRACTION
ECU
TRACTION ECU (
GND )
DOOR LOCK CONTROL
SW
MIRROR HEATER RH DOOR LOCK MOTOR,
D OOR UNL OC K
DETECTION SW AND
DOOR OPEN DETECTION
SW RH DOOR KEY LOCK AND
UNLOCK SW RH
HEADLIGHT LO LH
I25
I14 B33
B6
B7
HEADLIGHT LO RH
B20
B21
B29
E1
I11 I12 I13
IJ
BL
Bd1
2
Bb14
IJ113
IP1 20
IN1
1
IE2
12
IE1
19
BX1
10
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±B W±B W±B W±B W±B
W±B
W±B W±B W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±B
W±B
W±B
W±B W±B
W±B
(
W/ REAR SPOILER )
( W/O REAR SPOILER )
W±BW±B
W±B W±B
(
GN D2 )
( GN D3 )
( GN D2 )
( GN D3 )
(
GN D1 )
W±B
W±B
BR
I27
W±B
W±B
WOOFER SPEAKER
AMP LIFIER
BU28
(W/O CD PLAYER )
P±L BR
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109
WITH THE IGNITION SW TURNED ON, THE CURRENT FLOWS TO TERMINAL 7 OF THE INTEGRATION RELAY THROUGH GAUGE
FUSE. VOLTAGE IS APPLIED AT ALL TIMES TO TERMINAL (A)4 (USA), (B)11 (CANADA) OF THE INTEGRATION RELAY THROUGH THE
TAILLIGHT RELAY COIL, AND TO TERMINAL (A)5 (USA), (B)12 (CANADA) THROUGH THE HEADLIGHT RELAY COIL.
1. NORMAL LIGHTING OPERATION
TURN TAILLIGHT ON
WITH LIGHT CONTROL SW TURNED TO TAILLIGHT POSITION, A SIGNAL IS INPUT INTO TERMINAL (A)3 (USA), (B)10 (CANADA) OF
THE INTEGRATION RELAY. DUE TO THIS SIGNAL, THE CURRENT FLOWING TO TERMINAL (A)4 (USA), (B)11 (CANADA) OF THE RELAY
FLOWS TO TERMINAL (A)3 (USA), (B)10 (CANADA) " TERMINAL 3 OF THE LIGHT CONTROL SW "TERMINAL 4 " TO GROUND AND
TAILLIGHT RELAY CAUSES TAILLIGHT TO TURN ON.
TURN HEADLIGHT ON
WITH LIGHT CONTROL SW TURNED TO HEADLIGHT POSITION, A SIGNAL IS INPUT INTO TERMINALS (A)3 (USA). (B)10 (CANADA)
AND (A)6 (USA), (B)13 (CANADA) OF THE INTEGRATION RELAY. DUE TO THIS SIGNAL, THE CURRENT FLOWING TO TERMINAL (A)5
(USA), (B)12 (CANADA) OF THE RELAY FLOWS TO TERMINAL (A)6 (USA), (B)13 (CANADA) " TERMINAL 13 OF THE LIGHT CONTROL
SW " TERMINAL 4 " TO GROUND IN THE HEADLIGHT CIRCUIT, AND CAUSES TAILLIGHT AND HEADLIGHT RELAY TO TURN ON. THE
TAILLIGHT CIRCUIT IS SAME AS ABOVE.
2. LIGHT AUTO TURN OFF OPERATION
WITH LIGHTS ON AND IGNITION SW TURNED OFF (INPUT SIGNAL GOES TO TERMINAL 7 OF THE RELAY), WHEN DOOR ON DRIVER'S
SIDE IS OPENED (INPUT SIGNAL GOES TO TERMINAL 6 OF THE RELAY), THE RELAY OPERATES AND THE CURRENT IS CUT OFF
WHICH FLOWS FROM TERMINAL (A)4 (USA), (B)11 (CANADA) OF THE RELAY TO TERMINAL (A)3 (USA), (B)10 (CANADA) IN TAILLIGHT
CIRCUIT AND FROM TERMINAL (A)5 (USA), (B)12 (CANADA) TO TERMINAL (A)6 (USA), (B)13 (CANADA) IN HEADLIGHT CIRCUIT.
AS A RESULT, ALL LIGHTS ARE TURNED OFF AUTOMATICALLY.
HEADLIGHT RELAY 1±2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION
TAILLIGHT RELAY 5±3 : CLOSED WITH LIGHT CONTROL SW AT TA I L OR HEAD POSITION
I16(A)(B) INTEGRATION RELAY
7±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
6±GROUND : CONTINUITY WITH DOOR LH OPEN
(A) 4, (B) 11±GROUND: ALWAYS APPROX. 12 VOLTS
(A) 5, (B) 12±GROUND: ALWAYS APPROX. 12 VOLTS
(A) 6, (B) 13±GROUND: CONTINUITY WITH LIGHT CONTROL SW AT HEAD POSITION
(A) 3, (B) 10±GROUND: CONTINUITY WITH LIGHT CONTROL SW AT TA I L OR HEAD POSITION
D10 DOOR LOCK MOTOR, DOOR UNLOCK DETECTION SW AND DOOR OPEN DETECTION SW LH
3±6 : CLOSED WITH DOOR LH OPEN
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C1528F 926I16B29 (CANADA)
D1030I16A29 (USA)
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
423LEFT KICK PANEL (J/B NO.1 LEFT)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1J20COWL WIRE1K20COWL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IE136ENGINE WIRE AND COWL WIRE (R/B NO.4)
SYSTEM OUTLINE
SERVICE HINTS
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567 8
1LEXUSSC300(
Cont ' d )
2EC2 1EC2
7IJ1
1
345
12
B±O
B B
B±O
21
B±O
B±O
BL
B±O
W± L
B±O
W±Y
Y± G
W±Y
Y±G To Engine and ECT ECU º IGT1º < 2±8>
To Engine and ECT ECU º IGF1º < 2±8>
To Check Connec tor º IG±º < 2±4>
IGF IGT +B C±
TAC
I2
IGNITER
NO. 1
I4
IGNITION COIL
NO. 1DI STRI B UT OR
N3
NOISE FILTER
(
for Ignition System )
Ignition
B±O
8IK1 ToComb. MeterºTACHOº<21±7>
B± OB
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567 8
4LEXUSSC300(
Cont ' d )
1
2
1
2 1D
11 E 1I
10
3G
1
1B
2
3A
9
1C
10
1E
20
1H
1
9BU1
1Bd15IG7
11 Bc 1
Be1 2 1
1
2
3A
10
1 2
3 84
921117
3G
83A 2
3A
1
2
12
1
1
4
1
2 1
2
EA BM BL 2Bd14
1
3
8
2 10
3H
3
3C
3
3F
2
3G
5
3H
1
3F 6
1
2
1
3
2
2
9
5
1
10
F 5
G
IQ1
2
6
7 IQ1
4
12
3A 9
3E 6
3E 6
3E
6
3H 2
3H 1
3H 1
2
10 11 1 2
GW±G
G
G
GW±G W± GW±G
GW±G
G±O
G±O
G±O
G±O
G±O W±G W± G W± G
W± G W± G
W± G
G± W
W± BY Y
G±O
G
G
W± L
G
G
G
GW±BW± B W± B W± B
G
Y
V± G
V± G Y
G±W
G± W
W±B
GGGG
G
W
G± W
G± W
B
W± B R± W
B
G±W G±W G±O
G±O
W± B W
W±GBR
Y± V L±B L
W±B
W± B
W± B
W±B
W±B
G
G
W± G W± G
W±B
±PK ±STP E HS +STP
ETCRLRVREILL±
7
G± O
G± O
+PK BWRN
T
15A
STOP
F3
LH
F4
RH
FRONT
CLEARANCE LI GHT
L3
LI GHT FAILURE SENSOR
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
S12
STOP LIGHT SW
To ABS ECU<8±3><9±4>
To Shif t Lock ECU< 15±2>
G2
GLOVE BOX
LI GHT SW
F5
LH
F6
RH
FRONT SIDE
MARKER LIGHT
L2
LI CE NCE
PLATE LIGHT
W± B W±B
W±BH9
HIGH MOUNT
STOP LIGHT
H8
HIGH MOUNT
STOP LIGHT A1
A/C CONTROL
ASSEMBLY
A15
A / C C ON TR OL SW
AND RADIO SW
RADIO AND PLAYER
( w/o CD Player )
R4
RADIO AND PLAYER
( w/ CD Player )
T1 2
TRACTION CUT SW AND
SEAT HEATER SW
C1 1
CIGARETTE LIGHTER
A21
A/T INDICATOR LIGHT E8
ECT PATTERN
SELECT SW
T1 5
TRIP SW AND THEFT DETERRENT
INDICATOR LI GHT
R9
RHEOSTAT
G1
GLOVE BOX
55
13 13W±B
W±B
W± B W± B W± B
R± W
G±R
R± W G±R G±RTAI L AND
STOP LIGHT
[REAR COMB.
LIGHT]
R1 0
LH
R1 1
RH
TAIL
ST OP
TAIL
ST OP
To Engine and ECT ECU< 2±3>
To Traction ECU< 8±8>
To Cr uise Control ECU< 16±4>
To Cruise c ont rol
ECU< 16±4>
To Po wer Se at E CU
(Driver' s )
< 11±5>
G± W
G±W
(
* 1 )
(
* 2 )
( * 2 )
(
* 1
)
C13 , C14
ED
H
H
H
H
I3C
1
17
2345
COMBINATI ON METER C12 , C14 IH R5 , R6
FG
12 34
5678910
12
3456
RADIO AND PLAYER
(
w/ o CD Pl ay er )
Taillight and Stop Light (
for USA )
Illumination(
for USA )
*2:
(
w/o Rear Spoiler )
*
1: (
w/ Rear Spoiler )
W
G±W
G± O
Fro nt s i de of
right fender Under t he
c ent er pillar RH
Back panel c ent er 23
G
W± G
H7
HA ZA RD SW
10 11 12 13 17 18 19 20 21
12345 6789
14 15 16
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16 C1 2 I
C1 4 H
COMBI NATI ON METER
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
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567 8
21 LEXUS SC300(
Cont ' d )
AIR BAG
CHA RGE
OIL
OIL LEVEL COOLANT
LEVEL REAR
LI GHT
PWR
ABS TRAC
TRAC OFF
CRUISE WASHER
O/ D OFF
FUEL
SEAT BELTP
R N D 2 L
A
C
C A
A
B
B
B
C
C
C
C
C
C
C
B C
C
B
B
BA
B
A
A
C
CA A A A A A A A
C
C
C
C C C A C C B B B B
B A A C C
10 : 00
BK 1E
18 3D
10
3A
1
1J
1 1K
12
IH IF ED
IK1
8
IK2 IK1
9
1
E
3
E
2
E
1
D
BU110
BU1
3
BU1
4 11
11
1
14
19
8
18
11
13 6
18
17
16
20
19
15
13
3
15 5
1
20 9
18 8
11
87 1 2 3 4 5 16 17
2
3
4
5 10 9
12 23 12 4 17 16 7
6
15
10 22 21
W± R
RY
B±O
Y±B
V± R
V±Y
R±W
L±R
W
R± Y B
V±W V
R
L±R
P±L
Y±B
B±Y
B± W
W±B BR
B
W± B W± B BR±B
Y± G
B
Y±G
BR±B
W± B
W±B
W±B
BR±B W± B BR
Y±G
WATER
TEMP.HI GH BEAM TURN
LH
RH
BRAKE DOOR
TACHO
TRI P
SPEED
ILLUMINATIONCHECK±
ENGINE
FUEL
See Taillight and
St op Light Sy stem
<4±6><5±6>
SeeEngineControlSystem
<2±3>
Se e ABS Sy st e m< 8± 7> < 9± 3>
See Cruise Control System
< 16±3>Se e ABS an d Tr act io n
Control System< 8±7>
SeeECTandA/TIndicator
System< 3±5>
D
F1 7 , F18 E
FUEL SENDER Y±B
B±Y
B±W 24
See SRS Airbag System< 15±4>
See Charging Sy stem< 1±2>
See Headlight Sys tem< 4±1> < 5±1>
See Turn Signal and
Hazard Warning
Light Sy stem< 7±3>
See ECT System< 3±5>
From Neutr al St art SW< 1±3>
See Interier Light System< 6±3> From Igniter º TACº < 1±5>
To Engine and ECT ECU< 2±7>
To Cruise Control ECU< 16±3>
To PPS ECU< 15±2> See Illumination System
<4±7><5±7>
See ECT and A/T Indic ator
Syst em< 3±6>
See Unlock and Seat Belt
Warning Syst em< 4±4> < 5±4>
W3
WATER TEMP.
SENDER
Combination Meter
1
COMBINATION METER C12 , C13 , C14
A
AB IG1
8
Under the
c ent er
pillar LH Under the
as htr ay LH
Lef t
kick panelRear side of
c ylinder head RH
C
2
G 2
F
1
F 14
L±R
P
P
SH OR T C ON NE CT OR
S2 2 G , S23 F L±R
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44
POWER SOURCE (Current Flow Chart)
The chart below shows the route by which current flows from the battery to \
each electrical source
(Fusible Link, Circuit Breaker, Fuse, etc.) and other parts.
The next page and following pages show the parts to which each electrica\
l source outputs current.
Taillight
Relay (Point Side)
30A AM260A MAIN 50A DEFOG
60A HEATER
7.5 TRAC
40A IG SW
120A ALT
Starter Relay
(Point Side)
Headlight Relay
(Point Side)
30A EFI
15A TEL
10A DOME
20A RADIO No. 1
25A HAZ±HORN
Theft Deterrent and
Door Lock ECU
15A HEAD RH
(USA) 15A HEAD LH
(USA)
Dimmer Relay
(Coil Side)
Starter
15A STOPIgnition SW
(AM1)
30A DOOR
15A TAIL
Alternator
ABS Motor Relay
(Point Side)
Defogger
Relay
Starter ABS
Actuator
10A MIR±HTR
15A ECU±B 7.5A PANEL
7.5 IGN
Engine ECU Traction Brake
Actuator
30A INJ
60A ABS No.1
Traction Brake
Main Relay
(Point Side)
ABS
Actuator Relay
30A POWER
Integration
Relay
100A AM1
Seat Heater
Relay (Point Side)
7.5 ALT SENCING
30A ABS No.2 Headlight
Relay
(Coil Side)
Traction Motor
Relay (Point Side)Traction Pump
and Motor Dimmer Relay
(Point Side) Ignition SW
(AM2)
Taillight
Relay (Coil Side)
15A HEAD (LH±LWR)
(CANADA)
15A HEAD (RH±LWR)
(CANADA)
Engine and
ECT ECU
15A HEAD (LH±UPR)
(CANADA)
15A HEAD (RH±UPR)
(CANADA) ABS and
Traction ECU
Battery
[LOCATION](1): J/B No. 1 (See page
20)(2): R/B No. 2 (See page 19)(3): R/B No. 4 (See page 23)
20
19 22
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