1995 TOYOTA SUPRA ignition

SYSTEM INSPECTION
1. SETTING OF THE THEFT DETERRENT SYSTEM
Setting Conditions
(a) Close all the doors.
(b) Close the engine hood and luggage compartment door.
(c) Remove the ignition key from the ignition key cylinder.
Setting Operation
When any of the following operations (a) or (c) is done, the theft deterrent indicator light will light up as de-
scribed.
(a) Lock the left or right front door using the key.
(All doors are locked by key±interlinked lock operation)
(b) With the rear doors locked and with one of the front doors locked, lock the other front door without
using the key (keyless door lock).
 
 Elapsed time after operation
 
 Indicator light
  Within about 30 seconds  Lights up
  After about 30 seconds  Blinks *1
*1: 1 sec. on, 1 sec. off
HINT: When the theft deterrent system is set, doors cannot be locked or unlocked with the door lock control
switch and the luggage compartment door cannot be unlocked with the luggage compartment door opener
switch.
2. CANCELLING OF THE THEFT DETERRENT SYSTEM IN THE SET CONDITION
Check if the theft deterrent indicator light is blinking.
Cancelling Operation
When any of the following operation (a), (b), (c) or (d) is done, the theft deterrent system is cancelled and
indicator light will go off.
(a) Unlock the left or right front door using the key.
(b) Insert the ignition key in the ignition key cylinder and turn it to the ACC or ON position.
(This is operative only when the theft deterrent system has never operated.)
(c) Unlock the luggage compartment door with the key. *
1
*1: The theft deterrent system is temporarily cancelled only while the luggage compartment door is
open. Approximately 2 seconds after the luggage compartment door is closed, the theft deterrent
system is reset.
± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEMBE±121

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

TERMINALS OF ECU
 No. Symbol Terminal Name No. Symbol Terminal Name
 T8±1 +B2 Power Source T9±1 +B1 Power Source
 T8±2 ACT± Door Lock Motor T9±2 ± ± 
 T8±3
 
 ACT+
 
 Door Lock Motor
 
 T9±3
 
 ±
 
 ±
 T8±4 E Ground 
T9 4
 
DSWL
 Luggage Compartment Door Courtesy
 T8±5 ± ± T9±4 DSWL 
Luggage Com artment Door Courtesy
Switch
 T8±6 RLY Power Main Relay T9±5 L1 Door Lock Control Switch (Lock) 
 T8±7
 
 IG
 
 Ignition Switch ºONº
 
 T9±6
 
 UL3
 
 Door Key Lock and Unlock Switch
 T8±8 ACC Ignition Switch ºACCº T9±7 DSWD Door Open Detection Switch
 T8±9 ± ± T9±8 UL1 Door Lock Control Switch (Unlock)
 
T9 9
 
LUG
 Luggage Compartment Door Key Lock T9±9 LUG Luggage Com artment Door Key Lock
and Unlock Switch
 T9±10 HEAD Headlight Control Relay 
 T9±11
 
 SH
 
 Theft Deterrent Horn
 T9±12 IND Security Indicator Light
 T9±13 ± ±
 T9±14 FOD Engine Hood Courtesy Switch  
LSWD
 
Door Unlock Detection Switch or Door T9±15 LSWD,
UL2 Door Unlock Detection Switch or Door
K L k d U l k S it h
T9±15
UL2Key Lock and Unlock Switch 
 T9±16
 
 ±
 
 ±
 T9±17 ± ±
 T9±18 ± ±
 T9±19 DSWP Door Open Detection Switch 
 T9±20
 
 KSW
 
 Key Unlock Warning Switch
 T9±21 LSWP Door Unlock Detection Switch
 T9±22 L2 Door Key Lock and Unlock Switch
 T9±23 TAIL Taillight Control Relay 
 T9±24
 
 HORN
 
 HORN Relay
 T9±25 SRLY Ignition Switch ºSTº
± BODY ELECTRICAL SYSTEMBE±125THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

STANDARD VALUE OF ECU TERMINAL
 Terminals Symbols Condition Standard Value
 
 T8±1±Ground
(+B2±Ground) 
 L±W±Ground
 
 Always
 
 10±14 V
 
 T8±2±T8±3
(ACT±±ACT+)
 
 LR±LY
 
 Ignition Switch is turned to ºOFFº position.
 
 Below 50

 
 

T8±6±T8
(RLY±PRLY)
 
 

R±L±Ground
 
 

Always
 
 

10±14 V
 
 
 
T8±7±Ground
(IG±Ground)
 
 
 
B±R±Ground
 
 
 
Ignition switch is turned to ºONº position.
 
 
 
10±14 V
 
 
T8±7±T8±4
(ACC±E) 
 LR±WB 
 Ignition switch is turned to ºACCº position. 
 10±14 V
 
 
T9±Ground
(+B1±Ground) 
 R±Ground 
 Always 
 10±14 V
 
 T9±4±T8±4
 
 
LG WB
 
 
Luggage compartment door courtesy switch ON
(door opened). 
 Below 1

 
 
T94T84
(DSWL±E) 
 
LG±WB 
 
Luggage compartment door courtesy switch OFF
(door closed). 
 1 M
or higher
 T9±5±T8±4 
RW WB
 Door lock control switch ºlockº position. Below 1
 
 
T95T84
(L1±E) 
 
RW±WB 
 Door lock control switch OFF or ºunlockº position.
 
 1 M
or higher
 T9±6±T8±4 GWB Door key lock and unlock switch ºunlockº position. Below 1

 
T96T84
(UL3±E) G±WB Door key lock and unlock switch OFF or ºlockº position. 1 M
or higher
 
 T9±7±T8±4
 
 
RB WB
 
 Door open detection switch (driver's) ON
(door opened). 
 Below 1

 
 
T97T84
(DSWD±E) 
 
RB±WB 
 Door open detection switch (driver's) OFF
(door closed). 
 1 M
or higher
 
 T9±8±T8±4
 
 GR WB
 
 Door lock control switch ºunlockº position.
 
 Below 1

 
T98T84
(UL1±E) 
GR±WB
 Door lock control switch OFF or ºlockº position 1 M
or higher
 T9±9±T8±4 
LWB
 Luggage compartment door key lock and unlock switch ON Below 1

 T99T84
(LUG±E) L±WB Luggage compartment door key lock and unlock switch OFF 1 M
or higher 
 T9±10±T8±4
(HEAD±E)
 
 RY±WB
 
 Light control switch other than ºHEADº position.
 
 10±14 V
 
 
 
T9±11±T8±4
(SH±E)
 
 
 
WL±WB
 
 
 
Always
 
 
 
10±14 V
BE±126± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

 Terminals Symbols Condition Standard Value
 
 
T9±12±Ground
(IND±Ground) 
 W±L±Ground
 
 Always
 
 Below 270

 T9±14±T8±4 
VR WB
 Engine hood courtesy switch ON (hood opened). Below 1
 
 
T9 14 T8 4
(FOD±E) 
 
VR±WB 
 Engine hood courtesy switch OFF (hood closed). 
 1 M
or higher
 T9±15±T8±4 LW W B Door unlock detection switch ON (door opened). Below 1

 
T9 15 T8 4
(LSWD±E) LW±WB Door unlock detection switch OFF (door closed). 1 M
or higher
 
T9 15 T8 4
  Door key lock and unlock switch ºunlockº position Below 1
 
 
T9±15±T8±4
(UL2±E) 
 W±WB 
 Door key lock and unlock switch OFF or ºlockº
position 
 1 M
or higher
   
Door open detection switch (passenger's) ON
 
Below 1
 
 T9±19±T8±4
 
 RL WB
 
 
Door oen detection switch ( assenger s) ON
(door opened). 
 
Below 1

 
T9 19 T8 4
(DSWP±E) 
RL±WB
 Door open detection switch (passenger's) OFF 1M
or higher
   
Door oen detection switch ( assenger s) OFF
(door closed). 
1 M
or higher
 T9±20±T8±4 
YWB
 Key unlock warning switch ON. Below 1

 
T9 20 T8 4
(KSW±E) Y±WB Key unlock warning switch OFF. 1 M
or higher
 
T9±21±T8±4
 
GB WB
 Door unlock detection switch ON (door opened). Below 1
 
 
T9 21 T8 4
(LSWP±E) 
 
GB±WB 
 Door unlock detection switch OFF (door closed).
 
 1 M
or higher
 
T9 22 T8 4
  Door key lock and unlock switch ºlockº position. Below 1

 
 
T9±22±T8±4
(L2±E) 
 
GY±WB 
 
Door key lock and unlock switch OFF or ºunlockº
position. 
 1 M
or higher
 
 T9±23±T8±4
(TAIL±E) 
 GW±WB
 
 Light control switch ºTAILº position.
 
 10±14 V
 
 T9±24±T8±4
(HORN±E) 
 LR±WB
 
 Horn switch OFF.
 
 10±14 V
 
 T9±25±Ground
(SRLY±Ground) 
 L±O±Ground
 
 Ignition switch is turned to ºSTº position.
(When park / neutral position switch ºPº position) 
 10±14 V
± BODY ELECTRICAL SYSTEMBE±127THEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM

INSPECTION PROCEDURE
HINT: This troubleshooting is based on the premise that engine cranking occurs.
If the engine does not crank, proceed to engine troubleshooting on page EG±381 or 487 (Vol. 1).
(See page IN±30).
(1)Remove instrument panel panel.
(See BO section.)
(2)Disconnect the ECU connector.
Measure voltage between terminal SRLY of theft
deterrent ECU connector and body ground when
ignition switch is turned on.
Voltage: 10 ± 14 V
Check and replace theft deterrent ECU.
Check voltage between terminal SRLY of theft deterrent and door lock
ECU connector and body ground.
Check and repair harness and connector between starter and theft deterrent and door lock ECU
± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEMBE±131

Horn Relay Circuit
CIRCUIT DESCRIPTION
When the theft deterrent system is activated, it causes the Tr in the ECU to switch on and off in approximately
0.2 sec. cycles. This switches the horn relay on and off, thus the horns blow (See the wiring diagram below).
In this condition, if any of the following operations is done, the Tr in the ECU goes off and the horn relay switches
off, thus stopping the horns from blowing:
(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±132± BODY ELECTRICAL SYSTEMTHEFT DETERRENT AND DOOR LOCK CONTROL SYSTEM