1997 TOYOTA SUPRA ignition

Z07373
Junction Block Side
Connector ºAº
Wire Harness Side
Connector ºBº BE-14
- BODY ELECTRICALIGNITION SWITCH AND KEY UNLOCK WARNING
SWITCH
1992 Author
: Date
:
1997 SUPRA (RM502U)
4. INSPECT RELAY CIRCUIT
Light Auto Turn Off System:
Remove the relay from junction block and inspect the connec-
tors on the wire harness and junction block side, as shown in
the chart.
Tester connectionConditionSpecified condition
A6 - GroundDriver's door courtesy switch OFFNo continuity
A6 - GroundDriver's door courtesy switch ONContinuity
A10 - GroundConstantContinuity
B1 - GroundLight control switch position OFF or TAILNo continuity
B1 - GroundLight control switch position HEADContinuity
B4 - GroundLight control switch position OFFNo continuity
B4 - GroundLight control switch position TAIL or HEADContinuity
A1 - GroundConstantBattery positive voltage
A7 - GroundIgnition switch position LOCK or ACCNo voltage
A7 - GroundIgnition switch position ONBattery positive voltage
B2 - GroundConstantBattery positive voltage
B3 - GroundConstantBattery positive voltage
If the circuit is as specified, try replacing the relay with a new
one.
If the circuit not as specified, inspect the circuits connected to
other parts.

Z07503
Wire Harness Side
Z09181
34
2 143
12 BE-18
- BODY ELECTRICALHEADLIGHT AND TAILLIGHT SYSTEM
1996 Author
: Date
:
1997 SUPRA (RM502U)
6. INSPECT DOOR COURTESY SWITCH CONTINUITY
(See page BE-28)
7. CANADA models only:
INSPECT D.R.L. MAIN RELAY CIRCUIT
Disconnect the connector from relay and inspect the connector
on wire harness side, as shown.
Tester connectionConditionSpecified condition
5 - GroundHeadlight dimmer switch position Low beam or
high beamNo continuity
5 - GroundHeadlight dimmer switch position FlashContinuity
8 - GroundParking brake switch position OFFNo continuity
8 - GroundParking brake switch position ONContinuity
16 - GroundHeadlight dimmer switch position Low beamNo continuity
16 - GroundHeadlight dimmer switch position Flash or High
beamContinuity
13 - GroundConstantContinuity
18 - GroundConstantContinuity
2 - GroundIgnition switch position LOCK or ACCNo voltage
2 - GroundIgnition switch position ONBattery positive voltage
11 - GroundEngine StopNo voltage
11 - GroundEngine RunningBattery positive voltage
15 - Ground
17 - GroundConstantBattery positive voltage
If the circuit is as specified, try replacing the relay with a new
one.
If the circuit is not as specified, inspect the circuit connected to
other parts.
8. INSPECT D.R.L. NO.2 RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant3 - 4Continuity
Apply B+ between
terminals 3 and 4.1 - 2Continuity
If continuity is not as specified, replace the relay.

Z07379
Junction Block Side
- BODY ELECTRICALINTERIOR LIGHT SYSTEM
BE-29
2007 Author
: Date
:
1997 SUPRA (RM502U)
6. INSPECT INTEGRATION RELAY CIRCUIT
Remove the relay from junction block and inspect the connector
on the junction block side, as shown in the chart.
Tester connectionConditionSpecified condition
4 - GroundCourtesy Switch Position OFF (Door closed)No continuity
4 - GroundCourtesy Switch Position ON (Door opened)Continuity
10 - GroundConstantContinuity
1 - GroundConstantBattery positive voltage
7 - GroundIgnition switch position / LOCK or ACCNo voltage
7 - GroundIgnition switch position / ONBattery positive voltage
If circuit is as specified, try replacing the relay with a new one.
If the circuit is not as specified, inspect the circuits connected
to other parts.
7. INSPECT DOOR KEY LOCK AND UNLOCK SWITCH
CIRCUIT
See page DI-656
8. INSPECT DOOR UNLOCK DETECTION SWITCH CIR-
CUIT
See page DI-638

N08931
N08967
Ignition
Switch
Fuel
Gauge
Battery
Z09321
Fuel Gauge
Battery BE-44
- BODY ELECTRICALCOMBINATION METER
2022 Author
: Date
:
1997 SUPRA (RM502U)
4. INSPECT OD/TRIP METER (in Telltale Light RH)
(a) Remove the telltale light with connector still connected.
(b) Check the continuity and voltage.
Tester connectionConditionSpecified condition
7 - Ground*1ConstantContinuity
1 - Ground*1Ignition Switch ºONº positionBattery positive voltage
4 - Ground*1Light Control Switch ºTAILº or ºHEADº
positionBattery positive voltage
5 - 7*1Ignition Switch ON
Drive the vehicle slowly0V e Battery positive voltage
6 - 7*2Ignition Switch ON
Drive the vehicle slowly0V e more than 5V
8 - Ground*1ConstantBattery positive voltage
10 - Ground*1Ignition Switch ON, Light Control Switch TAIL or
HEAD, Turn the light control rheostat knob to
clockwise
6V " 0V
*1: If continuity or voltage are not as specified, check vehicle
side.
*
2: If voltage is not as specified, replace the telltale light.
5. INSPECT FUEL RECEIVER GAUGE OPERATION
(a) Disconnect the connector from the sender gauge assem-
bly.
(b) Turn the ignition switch ON, check that the receiver gauge
needle indicates EMPTY.
(c) Connect terminals 2 and 3 on the wire harness side con-
nector through a 3.4 W test bulb.
(d) Turn the ignition switch ON, and check that the bulb lights
up and that receiver gauge needle moves toward the full
side.
HINT:
Because of the silicon oil in the gauge, it will take a short time
for the needle to stabilize.
If operation is not as specified, inspect the receiver gauge resis-
tance.

N08911
B
AC
N08959
F
1/2
E
Z09401
Ignition
Switch
BatteryWarning Light
N08933
N08993
- BODY ELECTRICALCOMBINATION METER
BE-45
2023 Author
: Date
:
1997 SUPRA (RM502U)
6. INSPECT FUEL RECEIVER GAUGE RESISTANCE
Measure the resistance between terminals.
Between terminalsResistance (W)
A - BApprox. 269.7
A - CApprox. 123.5
B - CApprox. 146.2
If resistance value is not as specified, replace the fuel receiver
gauge.
7. INSPECT FUEL SENDER GAUGE RESISTANCE
Measure the resistance between terminals 2 and 3 for each
float position.
Float position: mm (in.)Resistance (W)
F: Approx. 33.8 (1.331)Approx. 4.0
1/2: Approx. 44.8 (1.764)Approx. 55.0
E: Approx. 141.1 (5.555)Approx. 107.0
If resistance value is not as specified, replace the sender
gauge.
8. INSPECT FUEL LEVEL WARNING LIGHT
(a) Disconnect the connector from the sender gauge.
(b) Connect terminals 1 and 3 on the wire harness side con-
nector.
(c) 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.
9. INSPECT FUEL LEVEL WARNING SWITCH OPERA-
TION
(a) Apply battery positive voltage between terminals 1 and 3
through a 3.4 W test bulb, check that the bulb lights up.
HINT:
It will take a short time for the bulb to light up.
(b) Submerge the switch in fuel, check that the bulb goes out.
If operation is not as specified, replace the sender gauge.

Z07423
Ignition
Switch
Battery Engine Coolant Temperature Gauge
Sender
Gauge
Z14747
Battery Engine Coolant Temperature Gauge
Test Bulb
(3W)
Z09421
A
BC
N15887
BE-46
- BODY ELECTRICALCOMBINATION METER
2024 Author
: Date
:
1997 SUPRA (RM502U)
10. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER 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 that 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 re-
sistance.
11. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER 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 terminalsResistance (W)
A - BApprox. 229.7
A - CApprox. 54.0
B - CApprox. 175.7
If resistance value is not as specified, replace the engine cool-
ant temperature receiver gauge.
12. INSPECT ENGINE COOLANT TEMPERATURE SEND-
ER GAUGE RESISTANCE
Measure the resistance between terminal and gauge body.
Temperature °C (°F)Resistance (W)
50 (122.0)160 ~ 240
120 (248.0)17.1 ~ 21.2
If resistance value is not as specified, replace the engine cool-
ant temperature sender gauge.

N06640
BE0044
Ignition
Switch
BatteryWarning Light
N09645
ON
OFF
N09646
ON
OFF
Z07431
Ignition
Switch
BatteryWarning Light
- BODY ELECTRICALCOMBINATION METER
BE-47
2025 Author
: Date
:
1997 SUPRA (RM502U)
13. INSPECT LOW OIL PRESSURE SWITCH CONTINUITY
(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.
14. INSPECT LOW OIL PRESSURE 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.
15. INSPECT ENGINE OIL LEVEL WARNING SWITCH
CONTINUITY
(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.
16. INSPECT ENGINE OIL LEVEL 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.

N08966
BE1217
Ignition
Switch
BatteryWarning Light
N09510
BE0044
Ignition
Switch
BatteryWarning Light BE-48
- BODY ELECTRICALCOMBINATION METER
2026 Author
: Date
:
1997 SUPRA (RM502U)
17. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
CONTINUITY
(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.
18. INSPECT BRAKE FLUID LEVEL 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.
19. INSPECT PARKING BRAKE SWITCH CONTINUITY
(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.
20. INSPECT PARKING BRAKE 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.