relay LEXUS SC300 1991 Service Repair Manual

49
F16 F18 I1H8
G2
G1 H1 H3 H2 H4 H5 I2 I14 I15 L7 I16 L2 M2L6
L3 M4
80
194
111 94 101
62
68
101 11 2
126
186 154
162
68 68 94
216
90 86
107
H6 H7 H9 98
N1
Unlock Warning SW
[Ignition SW] Igniter No.1 Fuel Pump ECU
Glove Box Light
Headlight LH HI
Hazard SW
High Mount Stop Light
(w/ Rear Spailer) Horn LHISC ValveIgnition Key Cylinder Light
Key Inter Lock Solenoid
Moon Roof Control Relay Light Failure Sensor
Luggage Compartment
Light SW
A/T Indicator SW
Back±Up Light SW
Neutral Start SW Licence Plate Light Integration Relay Fuel Sender
Glove Box Light SW
Headlight RH HI
Headlight LH LO
Headlight RH LO
Horn RH
High Mount Stop Light
(w/o Rear Spailer)
Luggage Compartment
Light SW
Moon Roof Motor
86
98
108
182
216
82
91
94
102
82
216 90
104
(4)
: R/B No. 5 (See page ) 22
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52
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
T9 T19T11 T12
T10 W5
V3 V5 V6 W3 W2
188
11 2
194
204 200
162 216
V4 200
112 90 134 68 156
192
226 94
VSV (for EVAP) Tension Reducer
Solenoid LHTheft
Deterrent and
Door Lock ECU
Tilt and power
Telescopic ECU
Seat Heater SW (A/T)
Traction Cut SWTrip SW and
Theft Deterrent Indicator
Telephone Transceiver and
Speaker Relay
Tension Reducer
Solenoid RHVSV
(for EGR)(EX. California)
Washer Level SW Vanity Light LH
Vanity Light RH
Washer Motor
Water Temp Sender
Wiper MotorVSV (
for Water Valve)
VSV (
for Fuel Pressure Up)
*Page Nos. of
Related Systems
Parts
Code or
Location
CB or Fuse
50A DEFOG
30A DOOR
30A POWER
15A STOP
15A ECU±B
10A MIR±HTR
10A HEATER
20A TURN
20A WIPER
10A GAUGE
15A ECU±IG
7.5A ENGINE
7.5A IGN
15A CIG
7.5A RADIO No.2
15A TAIL
7.5A PANEL
7.5A ST
15A TEL
10A DOME
20A RADIO No.1
25A HAZ±HORN
30A EFI
7.5A ALT SENCING
15A HEAD LH*1
15A HEAD RH*1
15A HEAD LH±LWR*2
15A HEAD RH±LWR*2
15A HEAD LH±UPR
15A HEAD RH±UPR
60A HEATER
7.5A TRAC
15A SEAT±HTR
Location
216
90
216
Traction ECU
Traction ECU
W1
V1 V2
T18
T16
T15
T14
T13
T8


* These are the page numbers of the first page on which the related system\
is shown.
The part indicated is located somewhere in the system, not necessarily o\
n the page indicated here.
[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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53
118 10422662
68
11 2
208
212
226 102
94
W7 W8 W10
Wireless Door Lock
Main SW
Wireless Door Lock ECU
Woofer Speaker Amplifier
Power Main Relay
A/C Magnetic Clutch Relay
EFI Main Relay
Heater Relay
Defogger Relay
Turn Signal Flasher
Horn Relay Diode
Cornering Light Relay Starter Relay
11 2
194 68
126 190
226
102
111
11 2
Diode
(4): R/B No. 5 (See page )
22
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56
POWER SOURCE
AM2 AM1
ACC
IG 1
IG 2
321 6 411
ST1
1B
2
1J 5
1J 6
1J 3
1J 8 1K
13
1K 4
1J
4
1B
4
1J
7 I24
I33
I11 P
N 2
3
IE1
16
IJ16
3421314 59 7
116
W
WB
B
B
B±R
B±W B±W
W±L
B
B±O P±L B
B
B
W±L R
W±R
W±R
B
W±R Y
W±L
W±R
W
W±R
B±Y
B±W P±L
B±O
B±W
B±W
B±W
B±WW
B±R
15A ECU±B
15A STOP
30A POWER
30A DOOR
TAILLIGHT
RELAY 15A TAIL
7. 5A PANEL BATTERY
15A ECU±IG
7. 5A ENGINE
20A W IPER
10A GAUGE 20A TURN
10A HEATER
7. 5A ST
7. 5A IGN 15A CIG
7. 5A RADIO NO. 2
40A
IGSW
NEUTRAL
START SW
TO ENGINE AND ECT ECUTO CRUISE CONTROL ECU
TO ABS ACTUATOR RELAY,
ABS MOTOR RELAY AND
TRACTION BRAKE
ACTUATOR RELAYTO ALTERNATOR º Bº
IGNITION SW
FUSE BLOCK
TO TRACTION MOTOR RELAY100A AM1
60A ABS NO. 1
30A INJ
120A ALT 30A AM2
30A ABS NO. 2 60A MAIN
F9
N1
I15
5
1 3
2
2
6
3 4 1
5
1 2IJ2
8 B
B±W
B
B
(
M/T )
(
M/T )
C23
CLUTCH START SW
(
A/T )
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57
87
65
43
21
10 9
12 11
14 13
21
22 21
20 19
18 17
16 15
2
2
2
2
2
2
2
2
2
2
2 2 22
2
2
2
2
2
22
2 2
2
IF 4
1B
1
4
4 2
2
4
4
EB1
3
W
B
B
B
B±R R±L
B
B
L±O R±Y L±R
WR
B±Y W
L±Y
W±L R
R
R
R±G R±B
R±W
B
R±Y
B
B
B±R
2
B
W±B B
R
1
212
1 2
2
4
3
1
1
3 43
1
3
5
2
2
4 4
3
5
3
4
20A RADIO NO. 1
25A HAZ±HORN 30A EFI
10A DOME
15A TEL
7. 5A ALT SENCING 7. 5A TRAC
HEADLIGHT
RELAY STARTER
RELAY
60A HEATER
50A DEFOGGER DEFOGGER
RE LA Y
15A SEAT±HTR
15A HEAD
(
LH±UPR )
15A HEAD (
RH±UPR )
15A HEAD (
LH )(
FOR USA )
15A HEAD (
LH±LWR )(
FOR CANADA )
15A HEAD (
RH )(
FOR USA )
15A HEAD (
RH±LWR )(
FOR CANADA )
DIMMER
RELAY
SEAT HEATER
RELAY 10A MIR±HTR
W±B I1W±B
B
(
M/T )
( A/T )
( CA NA DA )
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58
POWER SOURCE
HEADLIGHT RELAY (FOR USA)1±2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION
HEADLIGHT RELAY (FOR CANADA) 1±2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION
: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)
TAILLIGHT RELAY (FOR USA) 5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
TAILLIGHT RELAY (FOR CANADA) 5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)
IGNITION MAIN RELAY 2±1 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION
I15 IGNITION SW
4±3 : CLOSED WITH IGNITION KEY AT ACC OR ON POSITION
4±2 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION
11±6: CLOSED WITH IGNITION KEY AT ON OR ST POSITION
4±1 : CLOSED WITH IGNITION KEY AT ST POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C2328I1529
F 926N 127
: 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
1J20COWL WIRE1K20COWL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
EB134ENGINE WIRE AND ENGINE ROOM MAIN WIRE (FRONT SIDE OF R/B NO. 2)
IE136ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO. 4)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)IJ236ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 138COWL WIREI2438ENGINE ROOM MAIN WIRE
I1138COWL WIREI3338ENGINE WIRE
SERVICE HINTS
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122
POWER WINDOW
2
1H
10
1D
8 1J
11D 10 1D 91J 2
1B
5
1I
16
6 3 6
3
IF IJ IP1
20 IP1
15
B4 8
31
1I
7
24
A
20 A 8A2
A
16 A 13 A12 4
B 8
R
R
L±WB±R
W±B
W±B L
LW±B
R±B
R±W
W±B
W±B
W±B
W±B R±W
R±W
W±B
W±B
W±B
L
R±W
R±W
L
W±B W±B Y±R
10A
DOME
30A
DOOR15A
ECU±IG 30A
POWER
KEY OFF POWER
CIRCUIT POWER
MAIN
RELAY
DOOR OPEN
DE TE CTION SW RHDOOR OPEN
DE TECTION S W LH
THEFT DETERRENT
AND DOOR LOCK ECU
POWERWINDOWMASTERAND
DOOR LOCK CONTROL SW LH
DOOR LOCK
T8 ,T9
B A
1 2
1K
71K 13
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
D10
D11
P5
62
51
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124
POWER WINDOW
WITH THE IGNITION SW TURNED ON, CURRENT FLOWS THROUGH THE ECU±IG FUSE " TERMINAL (A)2 OF THE THEFT
DETERRENT ECU " (B)8 " TERMINAL 2 OF THE POWER MAIN RELAY " TERMINAL 3 " TO GROUND, THIS ACTIVATES THE RELAY
AND THE CURRENT FLOWING TO TERMINAL 4 OF THE RELAY FROM POWER FUSE FLOWS TO TERMINAL 1 OF THE RELAY "
TERMINAL 4 OF THE POWER WINDOW MASTER SW, TERMINAL 3 OF THE POWER WINDOW SW.
1. MANUAL OPERATION (DRIVER'S WINDOW)
WITH THE IGNITION SW TURNED ON AND WITH THE POWER WINDOW MASTER SW (DRIVER'S) IN UP POSITION, THE CURRENT
FLOWING TO TERMINAL 4 OF THE POWER WINDOW MASTER SW FLOWS TO TERMINAL 10 OF THE MASTER SW " TERMINAL 1 OF
THE POWER WINDOW MOTOR " TERMINAL 2 " TERMINAL 9 OF THE MASTER SW " TERMINAL 8 " TO GROUND AND CAUSES
THE POWER WINDOW MOTOR TO ROTATE IN THE UP DIRECTION. THE WINDOW ASCENDS ONLY WHILE THE SW IS BEING PUSHED.
IN DOWN OPERATION, THE FLOW OF CURRENT FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9 OF THE
MASTER SW CAUSES THE FLOW OF CURRENT FROM TERMINAL 2 OF THE MOTOR " TERMINAL 1 " TERMINAL 10 OF THE
MASTER SW " TERMINAL 8 " TO GROUND, FLOWING IN THE OPPOSITE DIRECTION TO MANUAL UP OPERATION AND CAUSING
THE MOTOR TO ROTATE IN REVERSE, LOWERING THE WINDOW.
2. DRIVER'S WINDOW AUTO DOWN OPERATION
WHEN THE DRIVER'S WINDOW SW IS PUSHED STRONGLY ON THE DOWN SIDE, THE CURRENT FLOWING TO TERMINAL 4 OF THE
POWER WINDOW MASTER SW FLOWS TO THE DOWN CONTACT POINT AND AUTO DOWN CONTACT POINT OF THE DRIVER'S SW.
THIS ACTIVATES THE RELAY (DOWN SIDE) INSIDE THE POWER WINDOW MASTER SW AND THE HOLD CIRCUIT ALSO TURNS ON AT
THE SAME TIME, SO THE RELAY (DOWN SIDE) REMAINS ACTIVATED EVEN WHEN THE SW IS RELEASED.
CURRENT FLOWS AT THIS TIME FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW " TERMINAL 9 " TERMINAL 2 OF
POWER WINDOW MOTOR " MOTOR " TERMINAL 1 " TERMINAL 10 OF POWER WINDOW MASTER SW " TERMINAL 8 " GROUND,
SO THE MOTOR CONTINUES TO OPERATE UNTIL THE DRIVER'S WINDOW IS FULLY DOWN.
WHEN THE DRIVER'S WINDOW FINISHES DOWN OPERATION THE HOLD CIRCUIT GOES OFF, SO THE RELAY (DOWN SIDE) ALSO
TURNS OFF. THIS STOPS THE CURRENT FLOW FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9, SO THE
POWER WINDOW MOTOR STOPS AND AUTO DOWN OPERATION STOPS.
WHEN THE DRIVER'S SW IS PULLED ON THE UP SIDE DURING AUTO DOWN OPERATION, THE HOLD CIRCUIT IS TURNED OFF SO
CURRENT FLOW FROM TERMINAL 4 OF THE POWER WINDOW MASTER SW TO TERMINAL 9 IS CUT OFF AND THE POWER WINDOW
MOTOR STOPS. IF THE SW REMAINS PULLED UP THE RELAY (UP SIDE) IS ACTIVATED, SO CURRENT FLOWS FROM TERMINAL 4 OF
THE POWER WINDOW MASTER SW " TERMINAL 10 " TERMINAL 1 OF POWER WINDOW MOTOR " MOTOR " TERMINAL 2 "
TERMINAL 9 " TERMINAL 8 " GROUND, THE POWER WINDOW MOTOR ROTATES IN THE UP DIRECTION AND MANUAL UP
OPERATION OCCURS WHILE THE SWITCH IS PULLED UP.
3. MANUAL OPERATION BY POWER WINDOW SW (PASSENGER'S WINDOW)
WITH POWER WINDOW SW (PASSENGER'S) PULLED TO THE UP SIDE, CURRENT FLOWING FROM TERMINAL 3 OF THE POWER
WINDOW CONTROL SW FLOWS TO TERMINAL 5 OF THE POWER WINDOW SW " TERMINAL 1 OF THE POWER WINDOW MOTOR "
TERMINAL 2 " TERMINAL 1 OF THE POWER WINDOW SW " TERMINAL 2 " TERMINAL 7 OF THE MASTER SW " TERMINAL 8 " TO
GROUND AND CAUSES THE POWER WINDOW MOTOR (PASSENGER'S) TO ROTATE IN THE UP DIRECTION. UP OPERATION
CONTINUES ONLY WHILE THE POWER WINDOW SW IS PULLED TO THE UP SIDE. WHEN THE WINDOW DESCENDS, THE CURRENT
FLOWING TO THE MOTOR FLOWS IN THE OPPOSITE DIRECTION, FROM TERMINAL 2 TO TERMINAL 1, AND THE MOTOR ROTATES IN
REVERSE. WHEN THE WINDOW LOCK SW IS PUSHED TO THE LOCK SIDE, THE GROUND CIRCUIT TO THE PASSENGER'S WINDOW
BECOMES OPEN.
AS A RESULT, EVEN IF OPEN/CLOSE OPERATION OF THE PASSENGER'S WINDOW IS TRIED, THE CURRENT FROM TERMINAL 8 OF
THE POWER WINDOW MASTER SW IS NOT GROUNDED AND THE MOTOR DOES NOT ROTATE, SO THE PASSENGER'S WINDOW CAN
NOT BE OPERATED AND WINDOW LOCK OCCURS.
4. KEY OFF POWER WINDOW OPERATION
WITH THE IGNITION SW TURNED FROM ON TO OFF, THE THEFT DETERRENT ECU OPERATES AND CURRENT FLOWS FROM DOOR
FUSE TO TERMINAL (A)8 OF THE ECU OR DOME FUSE TO TERMINAL (A)20 OF THE ECU " TERMINAL (B)8 " TERMINAL 2 OF
POWER MAIN RELAY " TERMINAL 3 " TO GROUND FOR ABOUT 60 SECONDS. THE SAME AS NORMAL OPERATION, THE CURRENT
FLOWS FROM POWER FUSE " TERMINAL 4 OF THE POWER MAIN RELAY " TERMINAL 1 " TERMINAL 4 OF THE POWER WINDOW
MASTER SW AND TERMINAL 5 OF THE POWER WINDOW SW. AS A RESULT, FOR ABOUT 60 SECONDS AFTER THE IGNITION SW IS
TURNED OFF, THE FUNCTIONING OF THIS RELAY MAKES IT POSSIBLE TO RAISE AND LOWER THE POWER WINDOW. ALSO, BY
OPENING THE FRONT DOOR (DOOR DETECT SW ON) WITHIN ABOUT 60 SECONDS AFTER TURNING THE IGNITION SW TO OFF, A
SIGNAL IS INPUT TO TERMINALS (A)12 OR (A)13 OF THEFT DETERRENT ECU. AS A RESULT, THE ECU TURNS OFF AND UP AND
DOWN MOVEMENT OF THE POWER WINDOW STOPS.
SYSTEM OUTLINE
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125
P 5 POWER WINDOW MASTER AND DOOR LOCK CONTROL SW LH
4±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
8±GROUND: ALWAYS CONTINUITY
10±GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON AND MASTER SW (DRIVER'S WINDOW) AT UP POSITION
9±GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON AND MASTER SW (DRIVER'S WINDOW) AT DOWN OR AUTO DOWN
POSITION
WINDOW LOCK SW
OPEN WITH WINDOW LOCK SW AT LOCK POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
D1029P 529T 8B29
D1129P 629T 9A29
P 429P 729
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IP138FRONT DOOR RH WIRE AND COWL WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IJ36RIGHT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
B 440FRONT DOOR LH WIRE
SERVICE HINTS
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160
POWER SEAT (w/ DRIVING POSITION MEMORY)
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
B532P11B32R1932
D1030P1232R2032
D1230P1332S1232
F1932P1432S1932
N 127P1532S2029
P 329P1632S2132
P 832P1732T1029
P 932P1832T1931
P10A32P1932
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1C20FLOOR WIRE
1D20FRONT DOOR LH WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF136FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IT138ENGINE WIRE AND A/C WIRE (BEHIND GLOVE BOX)
BT140FLOOR WIRE AND COWL WIRE (LEFT KICK PANEL)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
BX140FLOOR NO. 3 WIRE AND COWL WIRE (RIGHT KICK PANEL)
Ba142FLOOR WIRE AND FRONT SEAT LH WIRE (UNDER THE FRONT LH SEAT)Ba242FLOOR WIRE AND FRONT SEAT LH WIRE (UNDER THE FRONT LH SEAT)
Bb142FLOOR NO. 3 WIRE AND FRONT SEAT RH WIRE (UNDER THE FRONT RH SEAT)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IH36UNDER THE ASHTRAY LH
BK40UNDER THE CENTER PILLAR LH
BL40UNDER THE CENTER PILLAR RH
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 438COWL WIREB2742FRONT SEAT LH WIREI 538COWL WIREB2842FRONT SEAT LH WIRE
B 840FLOOR MAIN WIREB2942FRONT SEAT RH WIREB2642FRONT SEAT LH WIREB3042FRONT SEAT RH WIRE
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