1995 TOYOTA SUPRA relay

TROUBLESHOOTING
The table below will be useful for you in troubleshooting these electrical problems. The most likely causes
of the malfunction are shown in the order of their probability. Inspect each part in the order shown, and
replace the part when it is found to be faulty.
 Trouble Parts name (See page)
 
 
 
 
 
 
All defogger systems do not operate
 
 
 
 
 
 
1. GAUGE Fuse (BE±6)
2. DEFOG Fuse (BE±6)
3. Defogger Relay (BE±65)
4. Defogger Switch (BE±64)
5. A/C Amplifier (AC Section)
6. Wire Harness
 
 
Rear window defogger does not operate 
 
1. Defogger Wires (BE±65)
2. Wire Harness
 
 
 
Mirror defogger does not operate
 
 
 
1. MIR±HTR Fuse (BE±6)
2. Mirror Defogger (BE±66)
3. Wire Harness
DEFOGGER SWITCH INSPECTION
INSPECT SWITCH OPERATION
(a) Connect the positive (+) lead from the voltmeter to terminal
7 of connector B and the negative (±) lead from voltmeter to
terminal 10 of connector B.
(b) When the switch is off, the voltage should be approx. 12 V.
(c) When the switch is on, check that the indicator light lights up
and that the voltage is less than 1 V.
(d) After 15 minutes, check that the switch is off and the voltage
is approx. 12 V.
A/C AMPLIFIER INSPECTION
See A/C section BE±64
± BODY ELECTRICAL SYSTEMDEFOGGER SYSTEM

DEFOGGER RELAY INSPECTION
INSPECT RELAY CONTINUITY
 
 Condition
 
 Tester connection to
terminal number 
 Specified condition
 Constant 1±2  Continuity 
 
 
Apply B+ between
Terminals 1 and 2.
 
 
 
3±5
 
 
 
Continuity
If continuity is not as specified, replace the relay.
DEFOGGER WIRE INSPECTION
NOTICE:
wWhen cleaning the glass, use a soft, dry cloth, and
wipe the glass in the direction of the wire. Take care
not to damage the wires.
wDo not use detergents or glass cleaners with
abrasive ingredients.
w When measuring voltage, wind a piece of tin foil
around the top of the negative probe and press the
foil against the wire with your finger, as shown.
(a) Turn the ignition switch ON.
(b) Turn the defogger switch ON.
(c) Inspect the voltage at the center of each heat wire, as shown.
 Voltage Criteria
 Approx. 5V Okay (No break in wire)
 Approx. 10V or 0V Broken wire
HINT: If there is approximately 10 V, the wire is broken be-
tween the center of the wire and the positive (+) end. If there
is no voltage, the wire is broken between the center of the
wire and ground.
(d) Place the voltmeter positive (+) lead against the defogger
positive (+) terminal.
(e) Place the voltmeter negative (±) lead with the foil strip against
the heat wire at the positive (+) terminal end and slide it
toward the negative (±) terminal end.
(f) The point where the voltmeter deflects from zero to several
V is the place where the heat wire is broken.
HINT: If the heat wire is not broken, the voltmeter indicates
O V at the positive (+) end of the heat wire but gradually in-
creases to about 12 V as the meter probe is moved to the oth-
er end.
± BODY ELECTRICAL SYSTEMDEFOGGER SYSTEMBE±65

TROUBLESHOOTING
The table below will be useful for you in troubleshooting these electrical problems. The most likely causes
of the malfunction are shown in the order of their probability. Inspect each part in the order shown, and
replace the part when it is found to be faulty.
 Trouble Parts name (See page)
 
 
 
 
 
 
*1 Power window does not operate.
 
 
 
 
 
 
1. ALT Fuse (BE±5)
2. POWER Fuse (BE±5)
3. AM 1 Fuse (BE±5)
4. DOOR Fuse (BE±6)
5. Ignition Switch (BE±8)
6. Power Window Master Switch (BE±69)
7. Wire Harness
 
 
 
 
 
*2 Power Window does not operate.
 
 
 
 
 
1. GAUGE Fuse (BE±6)
2. Power Main Relay (BE±73)
3. Ignition Switch (BE±8)
4. Power Window Master Switch (BE±69)
5. Wire Harness
 ºOne Touch Power Window Systemº does not operate. 1. Power Window Master Switch (BE±69) 
 
 
 
Only one window glass does not move.
 
 
 
 
1. Power Window Master Switch (BE±69)
2. Power Window Switch (BE±71)
3. Power Window Motor (BE±71)
4. Wire Harness
 ºWindow Lock Systemº does not operate. 1. Power Window Master Switch (BE±69) 
 Illumination does not light up.
 
 1. Power Window Master Switch (BE±69)
*1 Power door lock does not operate.
*
2 Power door lock is normal. BE±68
± BODY ELECTRICAL SYSTEMPOWER WINDOW CONTROL SYSTEM

POWER MAIN RELAY INSPECTION
INSPECT RELAY CONTINUITY
 
 Condition
 
 
Tester connection to
terminal number 
 Specified condition
 Constant 1±2 Continuity 
 Apply B+ between
terminals 1 and 2.
 
 3±5
 
 Continuity
If continuity is not as specified, replace the relay.
± BODY ELECTRICAL SYSTEMPOWER WINDOW CONTROL SYSTEMBE±73

Glass printed
antenna faulty.
Motor antenna
faulty
AntennaANTENNA ± RELATED
Does antenna extend when radio
switched ON?
Inspect antenna motor.
Temporarily install another antenna
Functions OK?
Inspect glass printed antenna.
Radio side faulty.
Antenna motor faulty.
Relay faulty.
Relay circuit faulty.
Inspect antenna motor control relay.
(Relay circuit)
Is power released to the antenna being
input to the antenna motor control relay?
Radio side faulty.
Check continuity between antenna motor
control relay and radio.Wire harness faulty.
BE±110± BODY ELECTRICAL SYSTEMAUDIO SYSTEM

MOTOR ANTENNA CONTROL RELAY
INSPECTION
INSPECT RELAY CIRCUIT
Disconnect the connector from the relay and inspect connec-
tor on wire harness side, as shown in the chart.
 
 
Tester connection to
terminal number 
 Condition 
 Specified condition
 6±Ground Constant Continuity
 2±3 Constant Continuity 
 1±Ground
 
 Constant
 
 Battery positive voltage
 4±Ground Ignition switch position ON Battery positive voltage
 5±Ground Ignition switch position ACC or ON Battery positive voltage
 
 7±Ground
 
 Ignition switch position ACC or ON
and radio switch ON 
 Battery positive voltage
 8±Ground Ignition switch position ACC or ON Battery positive voltage
If circuit is not as specified, replace the relay.
± BODY ELECTRICAL SYSTEMAUDIO SYSTEMBE±113

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