1995 TOYOTA SUPRA engine

 Trouble Parts name (See page)
 
 Only one side light does not light 
 
1. Headlight Bulb
2. Wire Harness
 
 ºLo±Beamº does not light (ALL) 
 
1. Headlight Control Relay (BE±16)
2. Wire Harness
 
 
 
ºLo±Beamº does not light (ONE SIDE)
 
 
 
1. HEAD LH±LWR Fuse (BE±5)
2. HEAD RH±LWR Fuse (BE±5)
3. Headlight Bulb
4. Wire Harness
 
 
 
 
ºHi±Beamº does not light (ALL)
 
 
 
 
1. Headlight Dimmer Switch (BE±15)
2. Daytime Running Light Relay (BE±18)
3. Daytime Running Light No.2 and No.3 Relay (BE±19)
4. Wire Harness
 
 
 
 
ºHi±Beamº does not light (ONE SIDE)
 
 
 
 
1. HEAD LH±UPR Fuse (BE±5)
2. HEAD RH±UPR Fuse (BE±5)
3. Headlight Bulb
4. Wire Harness
 
 
 
 
ºFlashº does not light
 
 
 
 
1. Headlight Dimmer Switch (BE±15)
2. Daytime Running Light Relay (BE±18)
3. Daytime Running Light No.2 and No.3 Relay (BE±19)
4. Wire Harness
 
 
 
ºAuto Turn±off Systemº dose not operate
 
 
 
1. Integration Relay (BE±17)
2. GAUGE Fuse (BE±6)
3. Wire Harness
4. Door Courtesy Switch (driver's) (BE±28)
 
 
 
 
 
Headlight does not light with light control SW in HEAD.
 
 
 
 
 
1. Integration Relay (BE±17)
2. Light Control Switch (BE±15)
3. Daytime Running Light Relay (BE±18)
4. Daytime Running Light No.2 and No.3 Relay (BE±19)
5. Wire Harness
 
 Headlight does not go out with light control SW in OFF 
 
1. Headlight Control Relay (BE±16)
2. Wire Harness
 
 
 
 
Taillight does not light with light control SW in TAIL
 
 
 
 
1. Taillight Control Relay (BE±16)
2. Integration Relay (BE±17)
3. Light Control Switch (BE±15)
4. Wire Harness
 
 
 
Taillight does not go out with light control SW in OFFª
 
 
 
1. Taillight Control Relay (BE±16)
2. Integration Relay (BE±17)
3. Light Control Switch (BE±15)
4. Wire Harness
 
 
 
 
 
 
Headlight and Taillight do not light with engine running and
light control SW in OFF
 
 
 
 
 
 
1. GAUGE Fuse (BE±6)
2. Daytime Running Light Relay (BE±18)
3. Daytime Running Light No.2 and No.3 Relay (BE±19)
4. Wire Harness
5. Generator L Terminal
6. Parking Brake Switch (BE±52)
BE±12± BODY ELECTRICAL SYSTEMHEADLIGHT AND TAILLIGHT SYSTEM

DAYTIME RUNNING LIGHT MAIN RELAY
INSPECTION
INSPECT RELAY CIRCUIT
Disconnect the connector from relay and inspect the connec-
tor on wire harness side, as shown.
 
 Tester connection to
terminal number 
 Condition
 
 Specified condition
 
 5±Ground
 
 Headlight dimmer switch position Low
beam or high beam 
  No continuity
 5±Ground  Headlight dimmer switch position Flash Continuity 8±Ground Parking brake switch position OFF No continuity 8±Ground Parking brake switch position ON Continuity 
16±Ground
 
Headlight dimmer switch position Low beam
 
No continuity
 16±Ground Headlight dimmer switch position Flash or
High beam Continuity
 
 13±Ground
 
 Constant
 
 Continuity
 18±Ground Constant Continuity
 2±Ground Ignition switch position LOCK or ACC No voltage
 2±Ground Ignition switch position ON Battery positive voltage
 11±Ground Engine Stop No voltage
 11±Ground Engine Running Battery positive voltage
 15±Ground  
15±Ground
17 GroundConstantBattery positive voltage 17±Ground Constant Battery ositive voltage
If the circuit is as specified, trying replacing the relay with a
new one. If the circuit is not as specified, inspect the circuit
connected to other parts.
PARKING BRAKE SWITCH INSPECTION
See page BE±52 BE±18
± BODY ELECTRICAL SYSTEMHEADLIGHT AND TAILLIGHT SYSTEM

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.
METER, GAUGES AND ILLUMINATION
 Trouble Parts name (See page)
 
 
 
Tachometer, Fuel Gauge and Engine Coolant Tempera-
ture Gauge do not operate
 
 
 
1. GAUGE Fuse (BE±6)
2. Meter Circuit Plate (BE±44)
3. Wire Harness
 
 
 
Speedometer does not operate
 
 
 
1. Vehicle Speed Sensor (BE±46)
2. Meter Circuit Plate (BE±44)
3. Wire Harness
 
 
 
 
Tachometer does not operate
 
 
 
 
1. Igniter
2. ECM (EG Section)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
Fuel Gauge does not operate or abnormal operation
 
 
 
 
1. Fuel Receiver Gauge (BE±48)
2. Fuel Sender Gauge (BE±49)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
Engine Coolant Temperature Gauge does not operate or
abnormal operation
 
 
 
 
1. Engine Coolant Temperature Receiver Gauge (BE±50)
2. Engine Coolant Temperature Sender Gauge (BE±50)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
All illumination lights do not light up
 
 
 
 
1. TAIL Fuse (BE±6)
2. Light Control Rheostat (BE±54)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
Only one illumination light does not light up 
 
1. Bulb
2. Meter Circuit Plate (BE±44)
± BODY ELECTRICAL SYSTEMCOMBINATION METERBE±41

WARNING LIGHTS
 Trouble Parts name (See page)
 
 
 
 
 
Warning lights do not light up
(Except Discharge and Door Open)
 
 
 
 
 
1. Bulb
2. IGN Fuse (BE±6)
3. Ignition Switch (BE±8)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
6. Generator
 
 
 
 
 
 
Brake Warning Light does not light up
 
 
 
 
 
 
1. Bulb
2. Brake Fluid Level Warning Switch (BE±52)
3. Parking Brake Switch (BE±52)
4. Bulb Check Relay
5. Meter Circuit Plate (BE±44)
6. Wire Harness
 
 
 
 
 
Seat Belt Warning Light does not light up
 
 
 
 
 
1. Bulb
2. Seat Belt Buckle Switch (BE±56)
3. Integration Relay (BE±55)
4. Meter Circuit Plate (BE±44)
5. Wire Harness
 
 
 
 
Engine Oil Level Warning Light does not light up
 
 
 
 
1. Bulb
2. Engine Oil Level Switch (BE±51)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
Low Oil Pressure Warning Light does not light up
 
 
 
1. Bulb
2. Low Oil Pressure Warning Switch (BE±51)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
 
 
 
 
 
 
 
Door Open Warning Light does not light up
 
 
 
 
 
 
 
1. Bulb
2. DOME Fuse (BE±5)
3. Door Courtesy Switch (BE±54)
4. Luggage Room Light Switch (BE±28)
5. Integration Relay
6. Meter Circuit Plate (BE±44)
7. Wire Harness
 
 
 
 
Master Warning Light does not light up
 
 
 
 
1. Bulb
2. Telltale Light (BE±48)
3. Meter Circuit Plate (BE±44)
4. Wire Harness
BE±42± BODY ELECTRICAL SYSTEMCOMBINATION METER

TACHOMETER INSPECTION
INSPECT TACHOMETER
ON±VEHICLE
(a) Connect a tune±up test tachometer, and start the engine.
NOTICE: Reversing the connection of the tachometer
will damage the transistors and diodes inside.
(b) Compare the tester and tachometer indications.
If error is excessive, replace the tachometer.
RPM (DC 13.5 V, 25°C (77°F))
 Standard indication (rpm) Allowable range (rpm) 
 700
 
 630±770
 1000 915±1115
 2000 1920±2220
 3000 2890±3350 
 4000 
 3940±4400
 5000 5025±5425
 6500 6650±6950
 7000 7025±7625
± BODY ELECTRICAL SYSTEMCOMBINATION METERBE±47

ENGINE COOLANT TEMPERATURE
GAUGE INSPECTION
1. INSPECT RECEIVER GAUGE OPERATION
(a) Disconnect the connector from the sender gauge.
(b) Turn the ignition switch ON, check that the receiver gauge
needle indicates COOL.
(c) Ground terminal on the wire harness side connector through
a 3 W test bulb.
(d) Turn the ignition switch ON, check that the bulb lights up and
the receiver gauge needle moves toward the hot side.
If operation is as specified, replace the sender gauge.
Then recheck the system.
If operation is not as specified, measure the receiver gauge
resistance.
2. INSPECT RECEIVER GAUGE RESISTANCE
Measure the resistance between terminals.
HINT: Connect the test leads so that the current from the
ohmmeter can flow according to the chart order.
 Between terminals Resistance (
) 
A±B 
Approx. 229.7
 A±C Approx. 54.0
 B±C Approx. 175.7
If resistance value is not as specified, replace the engine
coolant temperature receiver gauge.
3. INSPECT SENDER GAUGE RESISTANCE
Measure the resistance between terminal and gauge body.
 Temperature °C (°F) Resistance (
)
 50 (122.0) 160 ~ 240
 120 (248.0) 17.1 ~ 21.2
If resistance value is not as specified, replace the engine
coolant temperature sender gauge. BE±50
± BODY ELECTRICAL SYSTEMCOMBINATION METER

LOW OIL PRESSURE WARNING
INSPECTION
1. INSPECT SWITCH
(a) Check that there is continuity between terminal and ground
with the engine stopped.
(b) Check that there is no continuity between terminal and
ground with the engine running.
HINT: Oil pressure should be over 29 kPa (0.3 kgf/ cm
2, 4.3
psi)
If operation is not as specified, replace the switch.
2. INSPECT WARNING LIGHT
(a) Disconnect the connector from the warning switch and
ground terminal on the wire harness side connector.
(b) Turn the ignition switch ON, check that the warning light lights
up.
If the warning light does not light up, test the bulb or inspect
wire harness.
ENGINE OIL LEVEL WARNING
INSPECTION
1. INSPECT SWITCH
(a) Check that there is continuity between terminal with the
switch in each position.
(b) Heat the switch to above 60°C (140°F) in an oil bath.
(c) Check that there is continuity between terminals with the
switch ON (float up).
(d) Check that there is no continuity between terminals with the
switch OFF (float down).
If operation is not as specified, replace the switch.
2. INSPECT WARNING LIGHT
(a) Disconnect the connector from the switch.
(b) Ground terminal 1 on the wire harness connector.
(c) Turn the ignition switch ON. Check that the warning light
lights up approximately 40 seconds later.
If the warning light does not light up, inspect bulb or wire har-
ness.
± BODY ELECTRICAL SYSTEMCOMBINATION METERBE±51

BRAKE FLUID LEVEL WARNING
INSPECTION
1. INSPECT SWITCH
(a) Remove the reservoir tank cap and strainer.
(b) Disconnect the connector.
(c) Check that there is no continuity between terminals with the
switch OFF (float up).
(d) Use syphon, etc. to take fluid out of the reservoir tank.
(e) Check that there is continuity between terminals with the
switch ON (float down).
(f) Pour the fluid back in the reservoir tank.
If operation is not as specified, replace the switch.
2. INSPECT WARNING LIGHT
(a) Disconnect the connector from the brake fluid warning
switch.
(b) Release the parking brake pedal.
(c) Connect terminals on the wire harness side of the level
warning switch connector.
(d) Start the engine, check that the warning light lights up.
If the warning light does not light up, test the bulb or wire har-
ness.
PARKING BRAKE WARNING
INSPECTION
1. INSPECT SWITCH
(a) Check that there is continuity between terminal and switch
body with the switch ON (switch pin released).
(b) Check that there is no continuity between terminal and switch
body with the switch OFF (switch pin pushed in).
If operation is not as specified, replace the switch or inspect
ground point.
2. INSPECT WARNING LIGHT
(a) Disconnect the connector from the parking brake switch and
the brake fluid warning switch.
(b) Ground terminal on the wire harness side connector.
(c) Start the engine, check that the warning light lights up.
If the warning light does not light up, test the bulb or inspect
wire harness. BE±52
± BODY ELECTRICAL SYSTEMCOMBINATION METER