1991 LEXUS SC400 relay

11 2
THEFT DETERRENT AND DOOR LOCK CONTROL
2
1I
14
1K
13
1K
11 2
3A
1
1J
1
1B
22
1H
13 3F
7
1E
18 1I
16 4
4
1D
8 1H
10 1B
5
1D 10 I8
I11
I11
B4
9
10
1 2IE1
6
IG1
17 IF2 15 IF214
IF2
16 IF2 18 IF2 5IF24
IF2
7
B
13
TAIL B
5
HE AD A
2
IG B
7
ACC A
20
+B1
A
16 E
A
6 KSW
A
19 TSW
A
14 L1
A
10 UL3
A
13 DSWD
A
11 LSWD
A
17 L2
A
18 UL2
1
13
6 4
7 24
2
31
8
21
IF 2 1
M
64 5 31 2
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
60A MAIN
120A ALT
100A AM1
LOCK
UNLOCK
LOCK
UNLOCK
15A
ECU±IG 15A
CIG10A
DOME
HEA DLIGHT
RELAY
G±Y
G±Y
G±L
R±B
L±W
L±R
W±B
W±B
W±B
W±L W
W
B±RL±R R
R
R±Y
G±W
W±B
Y
L
G±Y G G±Y
R±B
W±L
R±BG± L
R±B
G±L
L±W
L±W
R±W
L±W
L±W
R±BG±L
W±B L±R
W±B W±B W±B
G
G±Y L
W±B
W±B W±B
R±YTAI L LI GHT
RELAY
W±LW
TO FUSE º 15A TAILº
THEFT DETERRENT AND DOOR LOCK ECU
UNLOCK WA RNING SW
[IGNITION SW]
LUGGAGE COMPARTMENT
DOOR OPENER SW
DOOR KEY LOCK AND
UNLOCK SW LH
DOOR LOCK MOTOR,
DOOR UNLOCK DETE CTION AND
DOOR OPEN DETECTION SW LH
POWERWINDOWMASTERAND
DOOR LOCK CONTROL SW LH
FUSE BLOCK
L±R
BATTERY
F9
I15
L1
D7
D10
P5
T8 , T9 B A
DIODE
32 51 2
W±B
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11 4
THEFT DETERRENT AND DOOR LOCK CONTROL
2
5
1K
71E 5
44 1I
71J 1
3 11 IE1
9
2
1
BM IF BL
BT1
8BT1 7IG1 2IJ1
4
IJ1
9
B
11
HORN B
4
SH B
8
PRLY A
8
+B 2
B
1 LUG
B
10 DS WL
A
9 IND
4
I72
12
1
4
3
3
15
10 1 2
BY1
8
IH FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
25A
HAZ±HORN 30A
POWER30A
DOOR
POWER
MAIN
RELAY
W
WW W
G±R
WW
B±O
B±O
Y±RW±B
L±W
L±W
L±R
L±R
W±B W±B G±B
R±W L±G
L±G
R±W G±B
R
BR W±B
TRIP S W AND
THEFT DETERRENT
INDICATOR LIGHT
COMB INATION
METER
FUEL L I D
OPENER SOLENOID
FUEL LI D
OPENER SW
THEFT
DETERRENT
HORN
HORN
RELAY
LUGGAGE COMPARTMENT
LIGHT SW LUGGAGE COMPARTMENT
KEYUNLOCKSW
THEFT DETERRENT AND DOOR LOCK ECU T8
,T9 T1
F1 0
F1 4
T1 5
C14
L6 L5
B
A
B
6
52
31
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11 5
CURRENT ALWAYS FLOWS TO TERMINAL (A)8 OF THE DOOR LOCK ECU THROUGH THE DOOR FUSE, AND TO TERMINAL (A)20
THROUGH THE DOME FUSE.
WHEN THE IGNITION SW IS TURNED ON, THE CURRENT FLOWING THROUGH THE ECU±IG FUSE " TERMINAL (A)2 OF THE ECU "
TERMINAL (B)8 FLOWS THROUGH THE COIL SIDE OF THE POWER MAIN RELAY TO GROUND, CAUSING THE RELAY TO OPERATE.
THE CURRENT FLOWING THROUGH THE POWER FUSE FLOWS TO THE DOOR LOCK CONTROL SW LH, CAUSING THE INDICATOR
LIGHT TO LIGHT UP.
1. MANUAL LOCK OPERATION
WHEN THE DOOR CONTROL SW OR KEY SW ARE PUSHED TO LOCK POSITION, A LOCK SIGNAL IS INPUT TO TERMINAL (A)17, (A)14
(FOR KEY SW) OF THE DOOR LOCK ECU AND CAUSES THE ECU TO FUNCTION. CURRENT FLOWS FROM TERMINAL (A)8 OF THE
ECU " TERMINAL (A)4 " TERMINAL 5 OF THE DOOR LOCK MOTORS " TERMINAL 2 " TERMINAL (A)3 OF THE ECU " TERMINAL
(A)16 " TO GROUND AND THE DOOR LOCK MOTOR CAUSES THE DOOR TO LOCK.
2. MANUAL UNLOCK OPERATION
WHEN THE DOOR LOCK CONTROL SW OR KEY ARE PUSHED TO UNLOCK POSITION, AN UNLOCK SIGNAL IS INPUT TO TERMINAL
(A)18, (A)10 (FOR KEY SW LH) OR (A)15 (FOR KEY SW RH) OF THE DOOR LOCK ECU AND CAUSES THE ECU TO FUNCTION.
CURRENT FLOWS FROM TERMINAL (A)8 OF THE ECU " TERMINAL (A)3 " TERMINAL 2 OF THE DOOR LOCK MOTORS " TERMINAL
5 " TERMINAL (A)4 OF THE ECU "TERMINAL (A)16 " TO GROUND AND THE DOOR LOCK MOTOR CAUSES THE DOOR TO
UNLOCK.
WHEN UNLOCK OPERATION OCCURS USING THE LH DOOR KEY SW, PERFORMING THE UNLOCK OPERATION ONCE UNLOCKS
ONLY THE DRIVER'S DOOR. TO UNLOCK ALL THE OTHER DOORS TOGETHER, UNLOCK OPERATION MUST BE PERFORMED AGAIN
WITHIN 3 SECONDS OF THE FIRST OPERATION.
3. IGNITION KEY REMINDER OPERATION
* OPERATION OF DOOR LOCK BUTTON (OPERATION OF DOOR LOCK MOTORS)
WHEN THE IGNITION KEY IS IN THE CYLINDER (UNLOCK WARNING SW ON) AND THE DOOR IS OPENED AND LOCKED USING
DOOR LOCK BUTTON (DOOR LOCK MOTOR), THE DOOR IS LOCKED ONCE BUT EACH DOOR IS UNLOCKED SOON BY THE
OPERATION OF THE ECU. AS A RESULT OF ECU ACTIVATION, THE CURRENT FLOWS FROM TERMINAL (A)8 OF THE ECU "
TERMINAL (A)3 " TERMINAL 2 OF THE DOOR LOCK MOTORS " TERMINAL 5 " TERMINAL (A)4 OF THE ECU " TERMINAL (A)16
" TO GROUND AND CAUSES ALL THE DOORS TO UNLOCK.
THE SAME APPLIES TO OPERATION OF THE DOOR LOCK CONTROL SW AND DOOR LOCK KEY SW.
* KEY LESS LOCK OPERATION
WHEN THE IGNITION KEY IS STILL INSERTED IN THE CYLINDER (UNLOCK WARNING SW ON), THE DOOR IS OPEN AND UNLOCK
OPERATION IS PREVENTED BY KEEPING THE DOOR LOCK BUTTON PRESSED TO THE LOCK SIDE, THE DOOR IS KEPT IN THE
LOCK CONDITION. IF THE DOOR IS THEN CLOSED, A SIGNAL IS INPUT TO THE ECU FROM THE DOOR COURTESY SW. THIS
ACTIVATES THE ECU AND EACH DOOR IS UNLOCKED.
SYSTEM OUTLINE
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11 6
THEFT DETERRENT AND DOOR LOCK CONTROL
D 7, D 8 DOOR KEY LOCK AND UNLOCK SW LH, RH
1±2 : CLOSED WITH DOOR LOCK CYLINDER UNLOCKED WITH KEY
3±2 : CLOSED WITH DOOR LOCK CYLINDER LOCKED WITH KEY
D10, D11 DOOR LOCK MOTOR, DOOR UNLOCK DETECTION SW AND DOOR OPEN DETECTION SW LH, RH
1±4: CLOSED WITH UNLOCK POSITION
E 5 ENGINE HOOD COURTESY SW
1±2: CLOSED WITH ENGINE HOOD OPEN
I15 UNLOCK WARNING SW [IGNITION SW]
9±10: CLOSED WITH IGNITION KEY IN CYLINDER
L 5 LUGGAGE COMPARTMENT KEY UNLOCK SW
1±3: CLOSED WITH DOOR LOCK CYLINDER UNLOCK WITH KEY
L 6 LUGGAGE COMPARTMENT LIGHT SW
1±GROUND: CLOSED WITH DOOR OPEN
T 8(B) THEFT DETERRENT AND DOOR LOCK ECU
1±GROUND: CONTINUITY WITH LUGGAGE COMPARTMENT DOOR TO UNLOCK POSITION
12±GROUND: CONTINUITY WITH ENGINE HOOD OPEN
10±GROUND: CONTINUITY WITH LUGGAGE COMPARTMENT DOOR OPEN
7±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ACC OR ON POSITION
T 9(A) THEFT DETERRENT AND DOOR LOCK ECU
1±GROUND: APPROX. 12 VOLTS WITH SHIFT LEVER IN N OR P POSITION AND IGNITION SW AT ST POSITION
2±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
6±GROUND: CONTINUITY WITH IGNITION KEY IN CYLINDER
7±GROUND: CONTINUITY WITH FRONT RH DOOR TO UNLOCK POSITION
8±GROUND: ALWAYS APPROX. 12 VOLTS
10±GROUND: CONTINUITY WITH DOOR LOCK KEY SW LH TO UNLOCK POSITION
11±GROUND: CONTINUITY WITH FRONT LH DOOR TO UNLOCK POSITION
12±GROUND: CONTINUITY WITH FRONT RH DOOR OPENED
13±GROUND: CONTINUITY WITH FRONT LH DOOR OPENED
14±GROUND: CONTINUITY WITH DOOR LOCK KEY SW RH TO LOCK POSITION
15±GROUND: CONTINUITY WITH DOOR LOCK KEY SW RH TO UNLOCK POSITION
20±GROUND: ALWAYS APPROX. 12 VOLTS
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C1428F 926N 127
C2328F1028P 531
D 730F1430T 127
D 830I1529T 8B29
D 930L 129T 9A29
D1030L 430T1529
D1130L 530
E 526L 630
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
422LEFT 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
1E20INSTRUMENT PANEL WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
3A22INSTRUMENT PANEL WIRE3F22INSTRUMENT PANEL WIRE
SERVICE HINTS
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10
TROUBLESHOOTING
VOLTAGE CHECK
(a) Establish conditions in which voltage is present at thecheck point.
Example: ± Ignition SW on
± Ignition SW and SW 1 on
± Ignition SW, SW 1 and Relay on (SW 2 off)
(b) Using a voltmeter, connect the negative lead to a good ground point or negative battery terminal, and the
positive lead to the connector or component terminal.
This check can be done with a test light instead of a
voltmeter.
CONTINUITY AND RESISTANCE CHECK
(a) Disconnect the battery terminal or wire so there is novoltage between the check points.
(b) Contact the two leads of an ohmmeter to each of the check points.
If the circuit has diodes, reverse the two leads and check
again.
When contacting the negative lead to the diode positive side
and the positive lead to the negative side, there should be
continuity.
When contacting the two leads in reverse, there should be no
continuity.
(c) Use the volt/ohmmeter with high impedance (10 k W/V
minimum) for troubleshooting of the electrical circuit.
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11
FINDING A SHORT CIRCUIT
(a) Remove the blown fuse and disconnect all loads of thefuse.
(b) Connect a test bulb in place of the fuse.
(c) Establish conditions in which the test bulb comes on.
Example: ± Ignition SW on
± Ignition SW and SW 1 on
± Ignition SW, SW 1 and Relay on (Connect theRelay) and SW 2 off (or Disconnect SW 2)
(d) Disconnect and reconnect the connectors while watching the test bulb.
The short lies between the connector where the test
bulb stays lit and the connector where the bulb goes
out.
(e) Find the exact location of the short by lightly shaking the problem wire along the body.
CAUTION:
(a) Do not open the cover or the case of the ECU unlessabsolutely necessary. (If the IC terminals are touched,
the IC may be destroyed by static electricity.)
(b) When replacing the internal mechanism (ECU part) of the digital meter, be careful that no part of your body or
clothing comes in contact with the terminals of leads
from the IC, etc. of the replacement part (spare part).
DISCONNECTION OF MALE AND FEMALE
CONNECTORS
To pull apart the connectors, pull on the connector itself, not the
wire harness.
HINT: Check to see what kind of connector you are disconnecting
before pulling apart.
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15
ABBREVIATIONS
DISCONNECTION AND CONNECTION OF BOLT
TYPE CONNECTORS
For engine and ECT ECU in this vehicle, connectors are used
which require a bolt built into the connector to be screwed down to
securely connect the connector.
1. Disconnect the connectorAfter completely loosening the bolt, the two parts of the
connector can be separated.
NOTICE:
Do not pull the wire harness when disconnecting the
connector.
2. Connect the connector
NOTICE:
Before connecting the connector, always check that the
terminals are not bent or damaged.
(a) Match the guide section of the male connectorcorrectly with the female connector, then press them
together.
(b) Tighten the bolt. Make sure the connectors are completely connected,
by tightening the bolt until there is a clearance of less
than 1 mm (0.04 in.) between the bottom of male
connector and the end of female connector.
ABBREVIATIONS
The following abbreviations are used in this manual.
A/C = Air Conditioning O/D = Overdrive
ABS = Anti±Lock Brake System R/B = Relay Block
A/T = Automatic Transmission RH = Right±Hand
CB = Circuit Breaker SRS = Supplement Restraint System
COMB. = Combination SW = Switch
ECT = Electronic Controlled Transmission TDCL = Total Diagnostic Communication Link
ECU = Electronic Control Unit TEMP. = Temperature
EGR = Exhaust Gas Recirculation TRAC = Traction Control
FL = Fusible Link VSV = Vacuum Switching Valve
ISC = Idle Speed Control W/ = With
J/B = Junction Block W/O = Without
LH = Left-Hand
* The titles given inside the components are the names of the terminals (ter\
minal codes) and are not treatedas being abbreviations.
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105
TURN SIGNAL FLASHER
(4) 3 ± GROUND: CHANGES FROM APPROX. 12 VOLTS TO 0 VOLTS WITH IGNITION SW ON AND TURN SIGNAL SW LEFT, OR WITH
HAZARD SW ON
(4) 5 ± GROUND: CHANGES FROM APPROX. 12 VOLTS TO 0 VOLTS WITH IGNITION SW ON AND TURN SIGNAL SW RIGHT, OR WITH
HAZARD SW ON
(4) 4 ± GROUND: CONTINUITY WITH TURN SIGNAL SW LEFT, OR HAZARD SW ON
(4) 2 ± GROUND: CONTINUITY WITH TURN SIGNAL SW RIGHT, OR HAZARD SW ON
(4) 1 ± GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON OR HAZARD SW ON
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C13A28F 726R1031
C14B28F 826R1131
C1628H 729
: 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)
1A20ENGINE ROOM MAIN WIRE
1C20FLOOR WIRE
1E20INSTRUMENT PANEL WIRE
1H
1J20COWL WIRE
1K
20COWL WIRE
3A
3D22INSTRUMENT PANEL WIRE
3G
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IE136ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO. 4)
IG136INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO 5)IG236INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO. 5)
IQ138INSTRUMENT PANEL WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PANEL CENTER)IQ238INSTRUMENT PANEL WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PA N E L CENTER)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EA34FRONT SIDE OF RIGHT FENDER
EB34FRONT SIDE OF LEFT FENDER
IF36LEFT KICK PANEL
BM40BACK PANEL CENTER
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 738COWL WIREB1540FLOOR MAIN WIRE
SERVICE HINTS
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