1995 TOYOTA SUPRA headlights

3. CHECK OF THE THEFT DETERRENT SYSTEM OPERATION.
Check if the theft deterrent indicator light is blinking.
When any of the following operations (a) or (b) is done, the system sounds the horns and theft deterrent
horn and flashes the headlights and taillights for about one minute to alert. At the same time, the system
disconnects the starter motor circuit and locks all doors (if all doors are not locked, the system repeats door
locking operation every 2 seconds during the one minute alert time).
(a) Open the engine hood using the engine hood opener lever.
(b) Unlock any of the front or rear doors without key operation.
4. CANCELLING OF THE THEFT DETERRENT SYSTEM IN OPERATING CONDITION.
The theft deterrent operation can be cancelled when any of the following conditions is met:
 No. Condition Cancelling Operation 
 1
 
 Unlock left or right door with the key.
 
 
 2 Unlock doors with wireless door lock control system. 
 3 Insert key into ignition key cylinder and turn it to ACC or ON position. *2
 4 About 1 minute passes after theft deterrent operation begins. Automatic stop *1
*1: In this case, the theft deterrent system resets in about 2 seconds after if all doors are closed.
*
2: The alarm will be off, but the engine will not operate. To restart the engine, see No.1.
ECU TERMINAL VALUES MEASUREMENT
USING TOYOTA BREAK±OUT±BOX AND
TOYOTA HAND±HELD TESTER
1. Hook up the TOYOTA break±out box and TOYOTA handheld
tester to the vehicle.
2. Read the ECU input/output values by following the prompts
on the hand±held tester screen.
HINT: TOYOTA hand±held tester has a ºShapshotº func-
tion. This records the measured values and is effective in
the diagnosis of intermittent problems.
Please refer to the TOYOTA hand±held tester/TOYOTA
break±out±box operator's manual for further details. BE±122
± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

MATRIX CHART OF PROBLEM SYMPTOMS
Proceed to the reference page shown in the matrix chart below for each malfunction symptom and troubleshoot
for each circuit.
HINT: Troubleshooting of the theft deterrent system is based on the premise that the door lock control system
is operating normally. Accordingly, before troubleshooting the theft deterrent system, first make certain that the
door lock control system is operating normally.
Theft Deterrent System
 Details of Problem Inspecting Circuit *1 See Page
  1. Indicator light circuit BE±128
 
 
Th th ft d t t t t b t
 
 2. Luggage compartment door key
lock and unlock switch circuit 
 BE±142
 The theft deterrent system cannot be set 3. Luggage Room Light switch circuit BE±144 
 
 
 4. Door courtesy switch circuit
 
 BE±147
  5. Engine hood courtesy switch circuit BE±148
 The indicator light does not blink when system is set Indicator light circuit BE±128
 
 
 When the
system is
 
 
 
When the back door is
opened by a method other
than the key. 
 
 The system
does not
 
 
 
Luggage compartment door courtesy
switch circuit
 
 
 BE±144
 
 
system is
set 
 When the engine hood is
opened 
 
does not
Operate 
 Engine hood courtesy switch circuit
 
 BE±148
 
 
 
 Horns do not sound 
 Horn relay circuit 
 BE±132
 
 While the system
ii i
 
 
Theft deterrent horn does not
sound 
 
Theft deterrent horn circuit 
 
BE±134
 is in warning
operation Headlights do not flash Headlight control relay circuit BE±136
 o eration Taillights do not flash Taillight control relay circuit BE±138
  The starter cut is not cut off Starter relay circuit BE±130 
 
 When the
System is
 
 
 
It is not cancelled when the
ignition key is Turned to ACC
or ON position
 
 
 Ignition switch circuit
 
 
 BE±140
 
 
 
System is
Set 
 
 
It still operates when the back
door is Opened with the key
 
 
 
Luggage compartment door key lock
and unlock switch circuit
 
 
 
BE±142
 System is still set even when a rear door is open Door courtesy switch circuit BE±147
  Horns sound Horn relay circuit BE±132
 Even when the Theft deterrent horn sounds Theft deterrent horn circuit BE±134
 

Even when the
System is not set 
Headlights stay on 
Headlight control relay circuit 
BE±136 
 
 
 Taillights stay on
 
 Taillight control relay circuit
 
 BE±138
*1
: If numbers are given to the circuit proceed with troubleshooting in the order indicated by those numbers.
± BODY ELECTRICAL SYSTEMBE±123THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

Headlight Control Relay Circuit
CIRCUIT DESCRIPTION
When the theft deterrent system is activated, it causes the Tr in the ECU to switch on and off at approximately
0.2 sec. intervals. This switches the headlight control relay on and off, thus flashing the headlights (See the wir-
ing diagram below).
In this condition, if any of the following operations is done, the Tr in the ECU goes off and the headlight control
relay switches off, thus stopping the headlights flashing:
(1) The front LH or RH door is unlocked with a key.
(2) The ignition switch is turned to ACC or ON position.
(3) Approximately 1 minute elapses.
BE±136± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

INSPECTION PROCEDURE
HINT: The flow chart below is based on the premise that the headlights light up normally whenever the light con±
trol switch is operated. If headlight operation is not normal when the light control switch is operated, pro±
ceed to troubleshooting on page BE±11.
Check and replace theft deterrent and door lock
ECU.
Measure voltage between terminal HEAD of theft
deterrent ECU connector and body ground.
Voltage: 10 ± 14 V
Check and repair harness and connector between theft deterrent and door lock ECU headlight
control relay (See page IN±30).
Check voltage between terminal HEAD of theft deterrent and door lock
ECU connector and body ground.
(1) Remove instrument panel.
(See BO section)
(2) Disconnect the ECU connector.
± BODY ELECTRICAL SYSTEMBE±137THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

wConnect the positive (+) probe of the ammeter to
terminal B of the generator.
wConnect the positive (+) probe of the voltmeter to
terminal B of the generator.
wGround the negative (±) probe of the voltmeter.
(b) Check the charging circuit as follows:
With the engine running from idling to 2,000 rpm, check the
reading on the ammeter and voltmeter:
Standard amperage:
10 A or less
Standard voltage:
At 25°C (77°F)
13.6±14.8 V
At 115°C (239°F)
S13.2±14.0 V
If the voltmeter reading is more than standard voltage, re-
place the voltage regulator.
If the voltmeter reading is less than standard voltage, check
the voltage regulator and generator as follows:
wWith terminal F grounded, start the engine and check
the voltmeter reading of terminal B.
wIf the voltmeter reading is more than standard voltage,
replace the voltage regulator.
wIf the voltmeter reading is less than standard voltage,
check the generator.
8. 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,
repair the generator.
HINT: If the battery is fully charged, the indication will some-
times be less than standard amperage.
9. REINSTALL ENGINE UNDER COVER CH±6
± CHARGING SYSTEMON±VEHICLE INSPECTION

There are some maintenance and inspection
items which are considered to be the owner's re-
sponsibility. They can be performed by the owner
or be 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 perform. Items and procedures for gen-
eral maintenance are as follows:
OUTSIDE VEHICLE
1. TIRES
(a) Check the pressure with a gauge. Adjust if
necessary.
(b) Check for cuts, damage, uneven or excessive
wear.
2. WHEEL NUTS
When checking the tires, check the nuts for
looseness or for missing nuts. If necessary,
tighten them.
3. WINDSHIELD WIPER BLADES
Check for wear or cracks whenever they do not
wipe clean. Replace if necessary.
4. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or
other fluid.
(b) If you smell gasoline fumes or notice any leak,
have the cause found and corrected.
5. DOORS AND ENGINE HOOD
(a) Check that all doors including the trunk lid
operate smoothly, and that all latches lock
securely.
(b) Check that the engine hood secondary latch
secures the hood from opening when the
primary latch is released.
INSIDE VEHICLE
6. LIGHTS
(a) C h e c k t h a t t h e headlights, stop lights,
tail±lights, turn signal lights, and other lights
are all working.
(b) Check the headlight aiming.7. WARNING LIGHT AND BUZZERS
Check that all warning lights and buzzers
function properly.
8. HORN
Check that it is working.
9. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
10. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
11. WINDSHIELD DEFROSTER
Check that the air comes out from the defrost-
er outlet when operating the heater air condi-
tioner at defroster mode.
12. REAR VIEW MIRROR
Check that it is mounted securely.
13. SUN VISORS
Check that they move freely and are
mounted securely.
14. STEERING WHEEL
Check that it has the specified freeplay. Be
alert for changes in steering condition, such
as excessive steering effort, excessive free-
play or strange noise.
15. SEATS
(a) Check that all front seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly.
(b) Check that all latches lock securely in any
position.
(c) Check that the locks hold securely in any
latched position.
(d) Check that the head restraints move up and
down smoothly and that the locks hold
securely in any latched position.
(e) For folding±down rear seat backs, check that
the latches lock securely.
16. SEAT BELTS
(a) Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly.
(b) Check that the belt webbing is not cut, frayed,
worn or damaged.
17. ACCELERATOR PEDAL
Check the pedal for smooth operation and
uneven pedal effort or catching.
GENERAL MAINTENANCE
± MAINTENANCEGENERAL MAINTENANCEMA±17

When the problem seems to occur when the suspect
area is heated.HEAT METHOD:
Heat the component that is likely the cause of the mal-
function with a hair dryer or similar object. Check to see
if the malfunction will occur.
NOTICE:

Do not heat to more than 60°C (140°F) (Tempera±
ture limit that the component can be touched with
a hand.).

Do not apply heat directly to any part in the ECU.
WATER SPRINKLING
METHOD:When the malfunction seems to occur on a rainy day
or in a high±humidity condition.
Sprinkle water onto the vehicle and check to see if the
malfunction will occur.
NOTICE: Never apply water directly onto the elec-
tronic components.
HINT:

If the vehicle leaks water, the water may contaminate
the ECU. When testing a vehicle with a water leakage
problem, special caution must be paid.
OTHER:When the malfunction seems to occur when electrical load
is excessive.
Turn on all electrical loads including the heater blower,
headlights, rear window defogger, etc. and check to see
if the malfunction will occur.
± SUPPLEMENTAL RESTRAINT SYSTEMTROUBLESHOOTINGRS±49