1997 TOYOTA SUPRA headlights

I02544
LOCK
Disconnect
HEAD (+)
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
DI-627
855 Author
: Date
:
1997 SUPRA (RM502U)
INSPECTION PROCEDURE
HINT:
The flow chart below is based on the premise that the headlights light up normally whenever the light control
switch is operated. If headlight operation is not normal when the light control switch is operated, proceed
to troubleshooting on page BE-2.
1 Check voltage between terminal HEAD of theft deterrent and door lock ECU con-
nector and body ground.
PREPARATION:
(a) Remove the instrument panel. (See page BO-50)
(b) Disconnect the ECU connector.
CHECK:
Measure voltage between terminal HEAD of theft deterrent
ECU connector and body ground.
OK:
Voltage: 10 - 14 V
OK Check and replace theft deterrent and door lock
ECU.
NG
Check and repair harness and connector between theft deterrent and door lock ECU and head-
light control relay (See page IN-28).

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)

99
VOLTAGE IS ALWAYS APPLIED FROM THE MAIN FUSE, THROUGH THE HEADLIGHT RELAY (COIL SIDE) TO
TERMINAL 5 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN), TERMINAL 6 OF THE INTEGRATION RELAY,
TERMINAL 14 OF THE DIMMER SW, DIMMER RELAY (DAYTIME RUNNING LIGHT RELAY NO. 2) (COIL SIDE), TO
TERMINAL 17 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN). WHEN THE IGNITION SW IS TURNED ON, VOLTAGE
FROM THE GAUGE FUSE IS APPLIED TO TERMINAL 2 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN).
1. DAYTIME RUNNING LIGHT OPERATION
WHEN THE ENGINE STARTS, VOLTAGE FROM TERMINAL `L' OF THE GENERATOR IS APPLIED TO TERMINAL 11 OF
THE DAYTIME RUNNING LIGHT RELAY (MAIN). IF THE PARKING BRAKE LEVER IS PULLED UP (PARKING BRAKE SW
ON) AT THIS TIME, THE DAYTIME RUNNING LIGHT SYSTEM DOES NOT OPERATE. WHEN THE PARKING BRAKE IS
RELEASED (PARKING BRAKE SW OFF), A SIGNAL IS OUTPUT FROM TERMINAL 1 OF THE PARKING BRAKE SW TO
TERMINAL 8 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN). THIS ACTIVATES THE DAYTIME RUNNING LIGHT
RELAY (MAIN), TURNING ON THE DIMMER RELAY (DAYTIME RUNNING LIGHT RELAY NO. 2). CURRENT ALSO FLOWS
FROM THE MAIN FUSE TO THE DIMMER RELAY (DAYTIME RUNNING LIGHT RELAY NO. 2) (POINT SIDE) " HEAD
(LH-UPR) FUSE " HEADLIGHT HI LH " HEADLIGHT HI RH " TERMINAL (A)5 OF THE DAYTIME RUNNING LIGHT
RELAY NO. 3 " TERMINAL (A)3 " GROUND, CAUSING THE HEADLIGHTS TO LIGHT UP AT APPROX. 20% OF THEIR
NORMAL BRIGHTNESS.
ONCE THE DAYTIME RUNNING LIGHT RELAY (MAIN) HAS BEEN ACTIVATED AND THE HEADLIGHTS LIGHT UP, THE
HEADLIGHTS REMAIN ON EVEN IF THE PARKING BRAKE LEVER IS ENGAGED AGAIN (PARKING BRAKE SW ON).
2. HEADLIGHT OPERATION
WHEN THE LIGHT CONTROL SW IS AT HEAD POSITION AND THE DIMMER SW AT LOW POSITION, CURRENT FLOWS
FROM THE HEADLIGHT RELAY (COIL SIDE) TO TERMINAL 3 OF THE INTEGRATION RELAY " TERMINAL 4 "
TERMINAL 13 OF THE LIGHT CONTROL SW " TERMINAL 11 " GROUND, ACTIVATING THE HEADLIGHT RELAY.
THIS CAUSES THE CURRENT TO FLOW FROM THE HEADLIGHT RELAY (POINT SIDE) TO THE HEAD LWR FUSE "
HEADLIGHT LO " GROUND, CAUSING THE HEADLIGHTS TO LIGHT UP AT NORMAL BRIGHTNESS. SIMUTANEOUSLY,
CURRENT FLOWS FROM THE DRL FUSE " DAYTIME RUNNING LIGHT RELAY NO. 3 (COIL SIDE) " GROUND,
ACTIVATING RELAY NO. 3.
WHEN THE DIMMER SW IS AT HIGH POSITION, TERMINAL 12 OF THE DIMMER SW OUTPUTS A SIGNAL TO
TERMINAL 16 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN) TO ACTIVATE IT. THIS TURNS ON DIMMER RELAY
(DAYTIME RUNNING LIGHT RELAY NO. 2). SO CURRENT FLOWS FROM THE DIMMER RELAY (DAYTIME RUNNING
LIGHT RELAY NO. 2) (POINT SIDE) TO THE HEAD (LH-UPR) FUSE " HEADLIGHT HI LH " DAYTIME RUNNING LIGHT
NO. 3 (POINT SIDE) " GROUND, AND FROM THE HEAD (RH-UPR) FUSE " DAYTIME RUNNING LIGHT RELAY NO. 3
(POINT SIDE) " HEADLIGHT HI RH " DAYTIME RUNNING LIGHT RELAY NO. 3 (POINT SIDE) " GROUND, CAUSING
THE HEADLIGHTS TO OPERATE AT HI.
WHEN THE DIMMER SW IS AT FLASH POSITION, CURRENT FROM THE HEADLIGHT RELAY (COIL SIDE) FLOWS TO
TERMINAL 14 OF THE DIMMER SW " TERMINAL 9 " GROUND, ACTIVATING THE RELAY. SIMULTANEOUSLY,
CURRENT FROM THE HEADLIGHT RELAY (POINT SIDE) FLOWS TO HEADLIGHT LO, LIGHTING UP HEADLIGHT LO
AND ACTIVATING DAYTIME RUNNING LIGHT RELAY NO. 3. THEN TERMINAL 12 OF THE DIMMER SW OUTPUTS A
SIGNAL TO TERMINAL 16 OF THE DAYTIME RUNNING LIGHT RELAY (MAIN), ACTIVATING THE DAYTIME RUNNING
LIGHT RELAY (MAIN) SO THAT CURRNET FLOWS TO HEADLIGHT HI LIKE IT DOES FOR HIGH POSITION. THIS
CAUSES ALL HEADLIGHTS TO LIGHT UP.
D6 DAYTIME RUNNING LIGHT RELAY (MAIN)
15-GROUND : ALWAYS APPROX. 12 VOLTS
2-GROUND : APPROX. 12 VOLTS WITH TEH IGNITION SW AT ON POSITION
13-GROUND : ALWAYS CONTINUITY
5-GROUND : APPROX. 12 VOLTS WITH THE DAYTIME RUNNING LIGHT SYSTEM
DOES NOT OPERATE OR THE LIGHT CONTROL SW AT OFF OR TAIL POSITION
(WHEN THE CONNECTOR IS DISCONNECTED, ALWAYS APPROX. 12 VOLTS)
8-GROUND : CONTINUITY WITH THE PARKING BRAKE LEVER RELEASED
SYSTEM OUTLINE
SERVICE HINTS

MA01E-01
MA-2
- MAINTENANCEINSIDE VEHICLE
39 Author
: Date
:
1997 SUPRA (RM502U)
INSIDE VEHICLE
GENERAL MAINTENANCE
These are maintenance and inspection items which are considered to be the owner's responsibility.
They can be done by the owner or they can have them done at a service shop.
These items include those which should be checked on a daily basis, those which, in most cases, do not
require (special) tools and those which are considered to be reasonable for the owner to do.
Items and procedures for general maintenance are as follows.
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.

Failure to do even one item an cause the engine to run poorly and increase exhaust emissions.
2. LIGHTS
(a) Check that the headlights, stop lights, taillights, turn signal lights, and other lights are all working.
(b) Check the headlight aim.
3. WARNING LIGHTS AND BUZZERS
Check that all warning lights and buzzers function properly.
4. HORN
Check that it is working.
5. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
6. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
7. WINDSHIELD DEFROSTER
Check that air comes out from the defroster outlet when operating the heater or air conditioner.
8. REAR VIEW MIRROR
Check that it is mounted securely.
9. SUN VISORS
Check that they move freely and are mounted securely.
10. STEERING WHEEL
Check that it has the specified freeplay. Be alert for changes in steering condition, such as hard steering,
excessive freeplay or strange noises.
11. SEATS
(a) Check that the seat adjusters operate smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the head restraints move up and down smoothly and that the locks hold securely in any
latch position.
(d) For fold-down seat backs, check that the latches lock securely.
12. SEAT BELTS
(a) Check that the seat belt system such as the buckles, retractors and anchors operate properly and
smoothly.
(b) Check that the belt webbing is not cut, frayed, worn or damaged.

- CHARGINGCHARGING SYSTEM
CH-5
1528 Author
: Date
:
1997 SUPRA (RM502U)
10. INSPECT CHARGING CIRCUIT WITH LOAD
(a) With the engine running at 2,000 rpm, turn on the high
beam headlights and place the heater blower switch at
ºHIº.
(b) Check the reading on the ammeter.
Standard amperage: 30 A or more
If the ammeter reading is less than the standard amperage, re-
pair the generator.
HINT:
If the battery is fully charged the indication will sometimes be
less than standard amperage.
11. REINSTALL ENGINE UNDER COVER