1986 TOYOTA SUPRA wiring diagram

Check voltage between terminal M±REL of engine control module connector
and body ground.
Turn ignition switch ON.
Measure voltage between terminal M±REL of en-
gine control module connector and body ground.
Voltage: 9 Ð 14 V
Check and replace engine control module.
Check EFI No.1 Fuse.
Remove EFI No.1 fuse from R/B No.2.
Check continuity of EFI No.1 fuse.
Continuity
Check for short in the harness and all the compo-
nents connected to EFI No.1 fuse (See Electrical
Wiring Diagram).
EG±468± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

INSPECTION PROCEDURE
Check EFI No.1 Fuse.
Remove EFI No.1 fuse from R/B No.2.
Check continuity of EFI No.1 fuse.
Continuity
Check for short in the harness and all the com-
ponents connected to EFI No.1 fuse (See Electri-
cal Wiring Diagram).
Connect SST (check harness ªAº).
(See page EG±404)
SST 09990±01000
Measure voltage between terminal BATT of en-
gine control module connector and body ground.
Voltage: 9 Ð 14 V
Check and replace engine control module.
Check and repair harness or connector between
engine control module and EFI No.1 fuse, EFI No.1
fuse and battery.
Proceed to next circuit inspection shown on matrix
chart (See page
EG±408).
Check voltage between terminal BATT of engine control module connector
and body ground.
Are the diagnostic trouble codes still in the memory when the ignition switch
is turned OFF?
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±471

1
FOREWORD
This wiring diagram manual has been prepared to provide
information on the electrical system of the 1995 SUPRA.
Applicable models: JZA 80 Series
For service specifications and repair procedures of the above
models other than those listed in this manual, refer to the
following manuals:
Manual Name
Pub. No.
1995 SUPRA Repair Manual
Volume 1
Volume 2
1995 TOYOTA New Car Features
RM408U1
RM408U2
NCF109U
All information in this manual is based on the latest product
information at the time of publication. However, specifications
and procedures are subject to change without notice.
TOYOTA MOTOR CORPORATION
When handling supplemental restraint system components (removal,
installation or inspection, etc.), always follow the direction given in the repair
manuals listed above to prevent accidents and supplemental restraint
system malfunction.
NOTICE

2
INTRODUCTION
This manual consists of the following 11 sections:
No.
SectionDescription
A
INDEXIndex of the contents of this manual.
A
INTRODUCTIONBrief explanation of each section.
BHOW TO USE
THIS MANUALInstructions on how to use this manual.
CTROUBLE±
SHOOTINGDescribes the basic inspection procedures for electrical circuits.
DABBREVIATIONSDefines the abbreviations used in this manual.
E
GLOSSARY OF
TERMS AND
SYMBOLS
Defines the symbols and functions of major parts.
FRELAY LOCATIONSShows position of the Electronic Control Unit, Relays, Relay Block, etc.
This section is closely related to the system circuit.
GELECTRICAL
WIRING ROUTINGDescribes position of Parts Connectors, Splice points, Ground points, etc.
This section is closely related to the system circuit.
HPOWER SOURCE
(Current Flow Chart)Describes power distribution from the power supply to various electrical
loads.
INDEXIndex of the system circuits.
I
SYSTEM CIRCUITS
Electrical circuits of each system are shown from the power supply through
ground points. Wiring connections and their positions are shown and
classified by code according to the connection method. (Refer to the
section, ªHow to use this manualº).
The ªSystem Outlineº and ªService Hintsº useful for troubleshooting are also
contained in this section.
JGROUND POINTSShows ground positions of all parts described in this manual.
K
OVERALL
ELECTRICAL
WIRING DIAGRAM
Provides circuit diagrams showing the circuit connections.

3
HOW TO USE THIS MANUAL
This manual provides information on the electrical circuits installed on vehicles by
dividing them into a circuit for each system.
The actual wiring of each system circuit is shown from the point where the power source
is received from the battery as far as each ground point. (All circuit diagrams are shown
with the switches in the OFF position.)
When troubleshooting any problem, first understand the operation of the circuit where
the problem was detected (see System Circuit section), the power source supplying
power to that circuit (see Power Source section), and the ground points (see Ground
Points section). See the System Outline to understand the circuit operation.
When the circuit operation is understood, begin troubleshooting of the problem circuit
to isolate the cause. Use Relay Location and Electrical Wire Routing sections to find
each part, junction block and wiring harness connectors, wiring harness and wiring
harness connectors, splice points, and ground points of each system circuit. Internal
wiring for each junction block is also provided for better understanding of connection
within a junction block.
Wiring related to each system is indicated in each system circuit by arrows (from

, to ). When overall connections are required, see the Overall Wiring Diagram
at the end of this manual.

17
1. NORMALLY
OPENOpens 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
CLOSEDBasically, 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

246
HOW TO USE THIS MANUAL
OVERALL ELECTRICAL WIRING DIAGRAM

Junction Block (The number in the circle is the
J/B No. and connector code is shown beside
it). Junction Blocks are shaded to clearly
separate them from other parts (different junc-
tion blocks are shaded differently for further
clarification.).
Example:
Indicates related system.
Indicates the wiring harness and wiring har-
ness connector. The wiring harness with male
terminal is shown with arrows
Outside numerals are pin numbers.
is used to indicate different wiring and
connector, etc. when the vehicle model, engine
type, or specification is different.
Indicates a shielded cable.
Indicates and located on ground point.
The same code occuring on the next page
indicates that the wire harness is continuous. System Title
Indicates the wiring color.
Wire colors are indicated by an alphabetical code.
B = Black L = Blue R = Red
BR = Brown LG = Light Green V = Violet
G = Green O = Orange W = White
GR = Gray P = Pink Y = Yellow
The first letter indicates the basic wire color and
the second letter indicates the color of the stripe.
Indicates the connector to be connected to a
part (the numeral indicates the pin No.)
The position of the parts is the same as shown
in the wiring diagram and wire routing.
Indicates the pin number of the connector.
The numbering system is different for female
and male connectors.
The numbering system for the overall wiring dia-
gram is the same as above.
Indicates a Relay Block. No Shading is used and
only the Relay Block No. is shown to distinguish
it from the J/B.
247