TOYOTA SUPRA 1997 Service Repair Manual

12
C TROUBLESHOOTING
HOW TO REPLACE TERMINAL
(with terminal retainer or secondary locking device)
1. PREPARE THE SPECIAL TOOL
HINT: To remove the terminal from the connector, please
construct and use the special tool or like object shown
on the left.
2. DISCONNECT CONNECTOR
3. DISENGAGE THE SECONDARY LOCKING DEVICE OR
TERMINAL RETAINER
(a) Locking device must be disengaged before the terminal
locking clip can be released and the terminal removed
from the connector.
(b) Use a special tool or the terminal pick to unlock the
secondary locking device or terminal retainer.
NOTICE:
Do not remove the terminal retainer from connector body.
A For Non-Waterproof Type Connector
HINT: The needle insertion position varies according to
the connector's shape (number of terminals
etc.), so check the position before inserting it.
Case 1º
Raise the terminal retainer up to the temporary
lock position.
Case 2º
Open the secondary locking device.

13
C
For Waterproof Type Connector
HINT: Terminal retainer color is different
according to connector body.
Case 1º
Type where terminal retainer is
pulled up to the temporary lock
position (Pull Type).
Insert the special tool into the
terminal retainer access hole (
Mark)
and pull the terminal retainer up to
the temporary lock position.
HINT: The needle insertion position varies
according to the connector's shape
(number of terminals etc.), so check
the position before inserting it.
Case 2º
Type which cannot be pulled as far as
Power Lock insert the tool straight
into the access hole of terminal
retainer as shown.B
Example:
Terminal Retainer
:Connector Body
Black or White :Gray
Black or White :Dark Gray
Gray or White :Black

14
C TROUBLESHOOTING
(a) Insert the terminal.
HINT:
1. Make sure the terminal is positioned correctly.
2. Insert the terminal until the locking lug locks firmly.
3. Insert the terminal with terminal retainer in the
temporary lock position.
(c) Release the locking lug from terminal and pull the
terminal out from rear.
4. INSTALL TERMINAL TO CONNECTOR
5. CONNECT CONNECTORPush the terminal retainer down to the temporary lock
position.
(b) Push the secondary locking device or terminal retainer
into the full lock position.

15
C TROUBLESHOOTING
DISCONNECTION AND CONNECTION OF BOLT
TYPE CONNECTORS
For engine control module in this vehicle, connections are used
which require a bolt built into the connector to be screwed down
to securely connect the connector.
1. Disconnect the connector
After 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 connector
correctly 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.

16
ABBREVIATIONS D
ABBREVIATIONS
The follow abbreviations are used in this manual.
ABS = Anti-Lock Brake Systerm O/D = Overdrive
A/C = Air Conditioning PPS = Progressive Power Steering
ACIS = Acoustic Control Induction System R/B = Relay Block
A/T = Automatic Transmission RH = Right-Hand
COMB. = Combination SFI = Sequential Multiport Fuel Injection
ECU. = Electronic Control Unit SRS = Supplemental Restraint System
EGR = Exhaust Gas Recirculation SW = Switch
ESA = Electronic Spark Advance TEMP. = Temperature
EVAP = Evaporative Emission TRAC = Traction Control
J/B = Junction Block VSV = Vacuum Switching Valve
LH = Left-Hand w/ = With
M/T = Manual Transmission w/o = Without
* The titles given inside the components are the names of the terminals (terminal codes) and are not treated
as being abbreviations.

17
E GLOSSARY OF TERMS AND SYMBOLS
METER, ANALOG
Current flow activates a magnetic
coil which causes a needle to
move, thereby providing a relative
display against a background
calibration. LED (LIGHT EMITTING DIODE)
Upon current flow, these diodes
emit light without producing the
heat of a comparable light. IGNITION COIL
Convert low-voltage DC current
into high-voltage ingition current
for firing the spark plugs.
1. SINGLE
FILAMENT
GROUND
The point at which wiring attaches
to the Body, thereby providing a
return path for an electrical circuit;
without a ground, current cannot
flow.
Current flow causes a headlight
filament to heat up and emit light.
A headlight may have either a
single (1) filament or a double (2)
filament. BATTERY
Stores chemical energy and
converts it into electrical energy.
Provides DC current for the
auto's various electrical circuits.
CAPACITOR (Condenser)
A small holding unit for temporary
storage of electrical voltage.
CIRCUIT BREAKER
Basically a reusable fuse, a circuit
breaker will heat and open if too
much current flows through it.
Some units automatically reset when
cool, others must be manually reset.
DIODE
A semiconductor which allows
current flow in only one direction.
DIODE, ZENER
A diode which allows current
flow in one direction but blocks
reverse flow only up to a specific
voltage. Above that potential, it
passes the excess voltage.
This acts as a simple voltage
regulator.
PHOTODIODE
The photodiode is a
semiconductor which controls the
current flow according to the
amount of light.
FUSE
A thin metal strip which burns
through when too much current
flows through it, thereby stop-
ping current flow and protecting a
circuit from damage.
FUSIBLE LINK
A heavy-gauge wire placed in
high amperage circuits which
burns through on overloads,
thereby protecting the circuit.
The numbers indicate the cross-
section surface area of the wires.HORN
An electric device which sounds a
loud audible signal.
LIGHT
Current flow through a filament
causes the filament to heat up
and emit light.
METER, DIGITAL
Current flow activates one or
many LED's, LCD's, or fluoresent
displays, which provide a relative
or digital display.
MOTOR
A power unit which converts
electrical energy into mechanical
energy, especially rotary motion. CIGARETTE LIGHTER
An electric resistance heating
element.
DISTRIBUTOR, IIA
Channels high-voltage current
from the ignition coil to the
individual spark plugs.
2. DOUBLE
FILAMENT
HEADLIGHTS
FUEL
M
(for High Current Fuse or
Fusible Link.)
(for Medium Current Fuse)

18
E
1. NORMALLY
OPEN
Open 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 juction 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 cureent 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) and
a black dot or
octagonal (
) mark at
the juction as spliced
(joined) connections. RELAY, DOUBLE THROW
A relay which passes current
through one set of contacts or the
other.
SENSOR, SPEED
Uses magnetic impulses to open
and close a switch to create a
signal for activation of other
components.TRANSISTOR
A solid state device typically used
as an electronic relay; stops or
passes current depending on the
voltage applied at base.º SWITCH, WIPER PARK
Automatically returns wipers to
the stop position when the wiper
switch is turned off. SWITCH, MANUALSPEAKER
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) SPLICED
WIRES
(1) NOT
CONNECTED

19
+
F RELAY LOCATIONS
[Engine Compartment]
[Instrument Panel]

20
+
F
[Body]
[Seat]

21
F RELAY LOCATIONS
: J/B No. 1Left Kick Panel (See Page 18)