1997 TOYOTA SUPRA relay

IN0253
WRONG CORRECT
IN0252
WRONG CORRECT
IN0002
Example IN-6
- INTRODUCTIONREPAIR INSTRUCTIONS
6 Author
: Date
:
1997 SUPRA (RM502U)
(l) Observe the following precautions to avoid damage to the
following parts:
(1) Do not open the cover or case of the ECU, ECM,
PCM or TCM unless absolutely necessary. (If the IC
terminals are touched, the IC may be destroyed by
static electricity.)


(2) To disconnect vacuum hoses, pull on the end, not
the middle of the hose.
(3) To pull apart electrical connectors, pull on the con-
nector itself, not the wires.
(4) Be careful not to drop electrical components, such
as sensors or relays. If they are dropped on a hard
floor, they should be replaced and not reused.
(5) When steam cleaning an engine, protect the elec-
tronic components, air filter and emissions-related
components from water.
(6) Never use an impact wrench to remove or install
temperature switches or temperature sensors.
(7) When checking continuity at the wire connector, in-
sert the tester probe carefully to prevent terminals
from bending.
(8) When using a vacuum gauge, never force the hose
onto a connector that is too large. Use a step-down
adapter for adjustment. Once the hose has been
stretched, it may leak.
(m) Tag hoses before disconnecting them:
(1) When disconnecting vacuum hoses, use tags to
identify how they should be reconnected.
(2) After completing a job, double check that the vacu-
um hoses are properly connected. A label under the
hood shows the proper layout.
(n) Unless otherwise stated, all resistance is measured at an
ambient temperature of 20°C (68°F). Because the resis-
tance may be outside specifications if measured at high
temperatures immediately after the vehicle has been run-
ning, measurements should be made when the engine
has cooled down.

V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR1
Slightly shake the connector vertically and horizontally.
Slightly shake the wire harness vertically and horizontally.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thorough-
ly.
Apply slight vibration with a finger to the part of the sensor
considered to be the problem cause and check if the
malfunction occurs.Shake Slightly
Swing Slightly
Vibrate Slightly
HINT: Applying strong vibration to relays may result in open
relays. IN-22
- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
22 Author
: Date
:
1997 SUPRA (RM502U)
3. SYMPTOM SIMULATION
The most difficult case in troubleshooting is when there are no problem symptoms occurring. In such cases,
a thorough customer problem analysis must be carried out, then simulate the same or similar conditions and
environment in which the problem occurred in the customer's vehicle. No matter how much experience a
technician has, or how skilled he may be, if he proceeds to troubleshoot without confirming the problem
symptoms he will tend to overlook something important in the repair operation and make a wrong guess
somewhere, which will only lead to a standstill. For example, for a problem which only occurs when the en-
gine is cold, or for a problem which occurs due to vibration caused by the road during driving, etc., the prob-
lem can never be determined so long as the symptoms are confirmed with the engine hot condition or the
vehicle at a standstill. Since vibration, heat or water penetration (moisture) are likely causes for problems
which are difficult to reproduce, the symptom simulation tests introduced here are effective measures in that
the external causes are applied to the vehicle in a stopped condition.
Important Points in the Symptom Simulation Test:
In the symptom simulation test, the problem symptoms should of course be confirmed, but the problem area
or parts must also be found out. To do this, narrow down the possible problem circuits according to the symp-
toms before starting this test and connect a tester beforehand. After that, carry out the symptom simulation
test, judging whether the circuit being tested is defective or normal and also confirming the problem symp-
toms at the same time. Refer to the matrix chart of problem symptoms for each system to narrow down the
possible causes of the symptom.

- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN-25
25 Author
: Date
:
1997 SUPRA (RM502U)
5. PROBLEM SYMPTOMS TABLE
The suspect circuits or parts for each problem symptom are shown in the table below. Use this table to trou-
bleshooting the problem when a ºNormalº code is displayed in the diagnostic trouble code check but the
problem is still occurring. Numbers in the table indicate the inspection order in which the circuits or parts
should be checked.
HINT:
When the problem is not detected by the diagnostic system even though the problem symptom is present,
it is considered that the problem is occurring outside the detection range of the diagnostic system, or that
the problem is occurring in a system other than the diagnostic system.
Symptom
Suspect AreaSee page
Engine does not crank (Does not start)
No initial combustion (Does not start)
No complete combustion (Does not start)1. Starter and starter relay
1. ECM power source circuit
2. Fuel pump control circuit
3. Engine control module (ECM)
1. Starter signal circuit
2. Fuel pump control circuit1. Fuel pump control circuit
PROBLEM SYMPTOMS TABLE
1. Compression
2. Fuel pump control circuit 1. A/C signal circuit
2. Fuel pump control circuit 1. A/C signal circuit (Compressor circuit)
2. ECM power source circuit 1. Starter signal circuit
2. Fuel pump control circuit1. Starter signal circuit
2. Fuel pump control circuit
3. Compression
idling) Hot engine Cold engine (Difficult to start)Engine cranks normally (Difficult to start)

Problem Symptom
Page
Indicates the page where the flow chart for each circuit
is located.

Circuit Inspection, Inspection Order
Indicates the circuit which needs to be checked for each problem
symptom. Check in the order indicated by the numbers.

Circuit or Part Name
Indicates the circuit or part which needs to be checked.
ST-14,ST-15
DI-144
DI-148
SF-67
DI-141
EM-3
DI-825 DI-148
DI-148
DI-148
DI-148 DI-141
DI-141

IN-36
- INTRODUCTIONTERMS
36 Author
: Date
:
1997 SUPRA (RM502U) HO2S
Heated Oxygen SensorHeated Oxygen Sensor (HO2S)
IACIdle Air ControlIdle Speed Control (ISC)
IATIntake Air TemperatureIntake or Inlet Air Temperature
ICMIgnition Control Module-
IFIIndirect Fuel InjectionIndirect Injection
IFSInertia Fuel-Shutoff-
ISCIdle Speed Control-
KSKnock SensorKnock Sensor
MAFMass Air FlowAir Flow Meter
MAPManifold Absolute PressureManifold Pressure
Intake Vacuum
MCMixture Control
Electric Bleed Air Control Valve (EBCV)
Mixture Control Valve (MCV)
Electric Air Control Valve (EACV)
MDPManifold Differential Pressure-
MFIMultiport Fuel InjectionElectronic Fuel Injection (EFI)
MILMalfunction Indicator LampCheck Engine Light
MSTManifold Surface Temperature-
MVZManifold Vacuum Zone-
NVRAMNon-V olatile Random Access Memory-
O2SOxygen SensorOxygen Sensor, O2 Sensor (O2S)
OBDOn-Board DiagnosticOn-Board Diagnostic (OBD)
OCOxidation Catalytic ConverterOxidation Catalyst Converter (OC), CCo
OPOpen LoopOpen Loop
PAIRPulsed Secondary Air InjectionAir Suction (AS)
PCMPowertrain Control Module-
PNPPark/Neutral Position-
PROMProgrammable Read Only Memory-
PSPPower Steering Pressure-
PTOXPeriodic Trap OxidizerDiesel Particulate Filter (DPF)
Diesel Particulate Trap (DPT)
RAMRandom Access MemoryRandom Access Memory (RAM)
RMRelay Module-
ROMRead Only MemoryRead Only Memory (ROM)
RPMEngine SpeedEngine Speed
SCSuperchargerSupercharger
SCBSupercharger Bypass-
SFISequential Multiport Fuel InjectionElectronic Fuel Injection (EFI), Sequential Injection
SPLSmoke Puff Limiter-
SRIService Reminder Indicator-
SRTSystem Readiness Test-
STScan Tool-
TBThrottle BodyThrottle Body
TBIThrottle Body Fuel InjectionSingle Point Injection
Central Fuel Injection (Ci)
TCTurbochargerTurbocharger
TCCTorque Converter ClutchTorque Converter

AC0Q2-01
Z18473
Pressure Switch
ReceiverRadiator
Fan Relay
No. 1
Compressor
Radiator
Fan Relay
No. 2Junction Block No. 2

Magnetic Clutch Relay

Reater Main Relay
Ambient Temperature
Sensor
Air Conditioning Amplifier
Solar Sensor
Room Temperature
SensorAir Conditioning
Control Assembly
Evaporator
Expansion Valve
Water Valve
Heater Radiaor
Air Outlet ServomotorAir Inlet
Servomotor
Blower Motor
Blower Motor
Control Relay
Evaporator Temperature Sensor
Air Mix Servomotor
Engine Coolant Temperature Sensor AC-14
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2162 Author
: Date
:
1997 SUPRA (RM502U)
LOCATION

N11671
Defroster Nozzle
Water Valve CoverPlate
Water Valve
Heater Radiator
A/C Unit
Block Joint
Blower Motor
Control Relay
Blower Motor
Lower CaseEvaporator
Expansion
Valve Air Inlet
Servomotor
Evaporator Temperature
Sensor Heater Air Duct
Evaporator CoverVent Air DuctEngine Coolant
Temperature
SensorAir Outlet
ServomotorAir Mix
Servomotor AC-24
- AIR CONDITIONINGAIR CONDITIONING UNIT
2172 Author
: Date
:
1997 SUPRA (RM502U)

AC0QD-02
N08381
N08398
Expansion valve
N08384
- AIR CONDITIONINGAIR CONDITIONING UNIT
AC-27
2175 Author
: Date
:
1997 SUPRA (RM502U)
DISASSEMBLY
1. REMOVE AIR INLET SERVOMOTOR
(a) Disconnect the connector.
(b) Disconnect the control link.
(c) Remove the 3 screws and the air inlet servomotor.
2. REMOVE BLOWER MOTOR CONTROL RELAY
(a) Disconnect the connector.
(b) Remove the 3 screws and the blower motor control relay.
3. REMOVE BLOWER MOTER
(a) Disconnect the connector.
(b) Remove the 3 screws and blower motor.
4. REMOVE EVAPORATOR
(a) Remove the wire harness.
(b) Remove the foot air duct.
(c) Remove the A/C unit block joint.
(d) Remove the 6 screws and down and the lower cover.
(e) Remove the 4 screws and the evaporator cover.
(f) Pull out the evaporator.
HINT:
At the time of reassembly, please refer to the following item.
If the evaporator is replaced, add compressor oil to compressor.
Add 40cc (1.4 fl.oz)
Compressor oil: ND-OIL 8 or equivalent
(g) Pull out the evaporator temp.sensor from the evaporator.
(h) Using a hexagon wrench, remove the 2 bolts and sepa-
rate the evaporator and expansion valve.
Torque: 5.4 N´m (55 kgf´cm, 48 in.´lbf)
HINT:
At the time of reassembly, please refer to the following item.
Lubricate 4 new O-rings with compressor oil and install the
tubes.
5. REMOVE AIR MIX SERVOMOTOR
(a) Remove the defroster duct.
(b) Remove the 3 screws and the water valve cover.
(c) Disconnect the connector.
(d) Disconnect the control link.
(e) Remove the screws and the air mix servomotor.

AC0R6-01
N08742
AC-62
- AIR CONDITIONINGBLOWER MOTOR CONTROL RELAY
2210 Author
: Date
:
1997 SUPRA (RM502U)
BLOWER MOTOR CONTROL
RELAY
REMOVAL
1. REMOVE BLOWER MOTOR
(See page AC-59)
2. REMOVE BLOWER MOTOR CONTROL RELAY
(a) Disconnect the connector.
(b) Remove the 3 screws and the blower motor control relay.