ECO mode TOYOTA SUPRA 1995 Service User Guide

[1] CUSTOMER PROBLEM ANALYSIS
In troubleshooting, the problem symptoms must be confirmed accurately and all preconceptions must be
cleared away in order to give an accurate judgment. To ascertain just what the problem symptoms are, it is ex-
tremely important to ask the customer about the problem and the conditions at the time it occurred.
Important Points in the Problem Analysis
The following 5 items are important points in the problem analysis. Past problems which are thought to be unre-
lated and the repair history, etc. may also help in some cases, so as much information as possible should be
gathered and its relationship with the problem symptoms should be correctly ascertained for reference in trou-
bleshooting. A customer problem analysis table is provided in the troubleshooting section for each system for
your use.
Important Points in the Customer Problem Analysis
wWhat ..................... Vehicle model, system name
wWhen ..................... Date, time, occurrence frequency
wWhere ..................... Road conditions
wUnder what conditions?.............. Running conditions, driving conditions, weather conditions
wHow did it happen? ..................... Problem symptoms
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMSIN±21

GLOSSARY OF SAE AND TOYOTA TERMS
This glossary lists all SAE±J1930 terms and abbreviations used in this manual in compliance with SAE
recommendations, as well as their Toyota equivalents.
 
 
SAE ABBREVI±
ATIONS 
 SAE TERMS
 
 
TOYOTA TERMS
( ) ±± ABBREVIATIONS
 A/C Air Conditioning Air Conditioner
 ACL Air Cleaner Air Cleaner
AIRSecondary Air InjectionAir Injection (AI) AP Accelerator Pedal ± B+ Battery Positive Voltage +B, Battery Voltage BARO Barometric Pressure ±
 CAC Charge Air Cooler Intercooler
 CARB Carburetor Carburetor
 CFI Continuous Fuel Injection ±
 CKP Crankshaft Position Crank Angle
CLClosed LoopClosed Loop CMP Camshaft Position Cam Angle CPP Clutch Pedal Position ±
 CTOX Continuous Trap Oxidizer ±
 CTP Closed Throttle Position Idle ON (IDL ON)
 DFI Direct Fuel Injection (Diesel) Direct Injection (DI)
 DI Distributor Ignition ±
 
 
DLC1
DLC2
DLC3 
 
Data Link Connector 1
Data Link Connector 2
Data Link Connector 3 
 
1: Check Connector
2: Toyota Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
 DTC Diagnostic Trouble Code Diagnostic Code
 DTM Diagnostic Test Mode ±
 ECL Engine Control Level ±
 ECM Engine Control Module Engine ECU (Electronic Control Unit)
 ECT Engine Coolant Temperature Coolant Temperature, Water Temperature
(THW)
 
 
 
 
EEPROM
 
 
 
 
Electrically Erasable Programmable Read Only
Memory
 
 
 
 
Electrically Erasable Programmable Read Only
Memory (EEPROM),
Erasable Programmable Read Only Memory
(EPROM)
 
 
EFE 
 
Early Fuel Evaporation 
 
Cold Mixture Heater (CMH), Heat Control Valve
(HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR) EI Electronic Ignition Toyota Distributorless Ignition (TDI) EM Engine Modification Engine Modification (EM) EPROM Erasable Programmable Read Only Memory Programmable Read Only Memory (PROM)
 EVAP Evaporative Emission Evaporative Emission Control (EVAP)
 FC Fan Control ±
 FEEPROM Flash Electrically Erasable Programmable
Read Only Memory ±
 
 FEPROM
 
 Flash Erasable Programmable Read Only
Memory 
 ±
 FF Flexible Fuel ±
 FP Fuel Pump Fuel Pump
 GEN Generator Alternator
 GND Ground Ground (GND)
HO2SHeated Oxygen SensorHeated Oxygen Sensor (HO2S)
± INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMSIN±39

There are some maintenance and inspection
items which are considered to be the owner's re-
sponsibility. They can be performed by the owner
or be can have them done at a service shop.
These items include those which should be
checked on a daily basis, those which, in most
cases, do not require (special) tools and those
which are considered to be reasonable for the
owner to perform. Items and procedures for gen-
eral maintenance are as follows:
OUTSIDE VEHICLE
1. TIRES
(a) Check the pressure with a gauge. Adjust if
necessary.
(b) Check for cuts, damage, uneven or excessive
wear.
2. WHEEL NUTS
When checking the tires, check the nuts for
looseness or for missing nuts. If necessary,
tighten them.
3. WINDSHIELD WIPER BLADES
Check for wear or cracks whenever they do not
wipe clean. Replace if necessary.
4. FLUID LEAKS
(a) Check underneath for leaking fuel, oil, water or
other fluid.
(b) If you smell gasoline fumes or notice any leak,
have the cause found and corrected.
5. DOORS AND ENGINE HOOD
(a) Check that all doors including the trunk lid
operate smoothly, and that all latches lock
securely.
(b) Check that the engine hood secondary latch
secures the hood from opening when the
primary latch is released.
INSIDE VEHICLE
6. LIGHTS
(a) C h e c k t h a t t h e headlights, stop lights,
tail±lights, turn signal lights, and other lights
are all working.
(b) Check the headlight aiming.7. WARNING LIGHT AND BUZZERS
Check that all warning lights and buzzers
function properly.
8. HORN
Check that it is working.
9. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
10. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
11. WINDSHIELD DEFROSTER
Check that the air comes out from the defrost-
er outlet when operating the heater air condi-
tioner at defroster mode.
12. REAR VIEW MIRROR
Check that it is mounted securely.
13. SUN VISORS
Check that they move freely and are
mounted securely.
14. STEERING WHEEL
Check that it has the specified freeplay. Be
alert for changes in steering condition, such
as excessive steering effort, excessive free-
play or strange noise.
15. SEATS
(a) Check that all front seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly.
(b) Check that all latches lock securely in any
position.
(c) Check that the locks hold securely in any
latched position.
(d) Check that the head restraints move up and
down smoothly and that the locks hold
securely in any latched position.
(e) For folding±down rear seat backs, check that
the latches lock securely.
16. SEAT BELTS
(a) Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly.
(b) Check that the belt webbing is not cut, frayed,
worn or damaged.
17. ACCELERATOR PEDAL
Check the pedal for smooth operation and
uneven pedal effort or catching.
GENERAL MAINTENANCE
± MAINTENANCEGENERAL MAINTENANCEMA±17

IDLE AND OR 2500 RPM CO HC CHECK
HINT: This check is used only to determine whether or not the
idle CO/HC complies with regulations.
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system connected
(d) All accessories switched OFF
(e) All vacuum lines properly connected
HINT: All vacuum hoses for EGR system, etc. should be prop-
erly connected.
(f) SFI system wiring connectors fully plugged
(g) Ignition timing set correctly
(h) Transmission in neutral position
(i) Tachometer and CO/HC meter calibrated by hand
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180
SECONDS
4. INSERT CO/HC METER TESTING PROBE AT LEAST 40
cm (1.3 ft) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT
IDLE AND/OR 2,500 RPM
HINT: When performing the 2 mode (2,500 rpm and idle) test,
follow the measurement order prescribed by the applicable
local regulations.
± ENGINEENGINE MECHANICALEG±7

DTC
No.Number of
MIL BlinksCircuitDiagnostic Trouble Code Detecting Condition
EGR System
Malfunction
Fuel Pump
Control Signal
Switch Condition
Signal
(1) 3 sec. or more after engine starts, with closed throttle posi±
tion switch OFF (IDL1)
(2) Park/neutral position switch: OFF
(Shift position in ªRº, ªDº, ª2º, or ªLº position)
(3) A/C switch ON
(3) Open or short in diagnostic signal line (DI) of fuel pump
ECU with engine speed 1,000 rpm or less
(2 trip detection logic)*
4
(2) Open in input circuit of fuel pump ECU (FPC) with engine
speed 1,000 rpm or less
(2 trip detection logic)*
4
(1) Open or short in fuel pump circuit for 1 sec. or more with
engine speed 1,000 rpm or less
(2 trip detection logic)*
4
EGR gas temp. is 70°C (158°F) or less for 1 Ð 4 min. under
conditions (a) and (b):
(2 trip detection logic)*
4
(a) Engine Coolant temp.: 63°C (145°F) or more
(b) EGR operation possible (Example A/T in 3rd speed (5th for
M/T),
A/C ON, 96 km/h (60 mph), Flat road)
*1: ºONº displayed in the diagnostic mode column indicates that the Malfunction Indicator Lamp is lit up when
a malfunction is detected. ºOFFº indicates that the ºCHECKº does not light up during malfunction
diagnosis, even if a malfunction is detected. ºN.A.º indicates that the item is not included in malfunction
diagnosis.
*2: º
º in the memory column indicates that a diagnostic trouble code is recorded in the ECM memory when
a malfunction occurs. ºxº indicates that a diagnostic trouble code is not recorded in the ECM memory even
if a malfunction occurs. Accordingly, output of diagnostic results in normal or test mode is done with the
IG switch ON.
*3: Only for California specification vehicles. EG±396
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 
 
 

Open in EGR gas temp. sensor circuit

Short in VSV circuit for EGR

EGR hose disconnected, valve stuck

Clogged EGR gas passage

ECM
 
 
 
 
 
 
ON
 
 
 
 
 
 
ON
 
 
 
 
 
 

 
 
 
 
 
 
EG±453
 
 
 
 
 
 
 
 
 
 
 
 
 

Open or short in fuel pump ECU circuit

Fuel pump ECU

Fuel pump

ECM power source circuit

ECM
 
 
 
 
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 
 
 
 
 
ON
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
EG±457
 
 
 
 
 
 

A/C switch circuit

Throttle position sensor IDL circuit

Park/neutral position switch circuit

Accelerator pedal and cable

ECM
 
 
 
 
 
 
N.A.
 
 
 
 
 
 
OFF
 
 
 
 
 
 
X
 
 
 
 
 
 
EG±460
*4: This indicates items for which º2 trip detection logicº is used. With this logic, when a logic malfunction is first
detected, the malfunction is temporarily stored in the ECM memory. If the same case is detected again
during the second drive test, this second detection causes the Malfunction Indicator Lamp to light up.
The 2 trip repeats the same mode a 2nd time. (However, the IG switch must be turned OFF between the
1st trip and 2nd trip).
In the Test Mode, the Malfunction Indicator Lamp lights up the 1st trip a malfunction is detected.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±397

CIRCUIT DESCRIPTION (Cont'd)
DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN
Purpose of the driving pattern.
(a) To simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded.
(b) To check that the malfunction is corrected when the repair is completed confirming that diagnostic
trouble code is no longer detected.
Malfunction: (Main heated() Oxygen Sensor Detection
(Vehicle Speed)
80 km/h (50 mph)
64 km/h (40 mph)
It is vital that this test routine is adhered to detect the malfunction:
(1) Disconnect the EFI No.1 fuse (30 A) for 10 sec. or more, with IG switch OFF. Initiate test
mode (Connect terminal TE2 and E1 of data link connector 2 with IG switch OFF).
(2) Start the engine and warm up with all ACC switched OFF.
(3) Idle the engine for 3 min.
(4) Accelerate gradually within the range 1,300 ~ 1,700 rpm (dentered around 1,500 rpm) with
the A/C switched ON and D position for A/T (5th for M/T).
HINT:
Ensure engine rpm does NOT fall below 1200 rpm.

Gradually depress the accelerator pedal at a suitable rate to comply with the test
requirements on the above graph.

Never allow engine rpm to drop at any time during the test.
(5) Maintain the vehicle speed at 64 Ð 80 km/h (40 Ð 50 mph).
(6) Keep the vehicle running for Ð 2 min. after starting acceleration.
HINT: If a malfunction exists, the Malfunction Indicator Lamp will light up after approx. 60 sec.
from the start of acceleration.
NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction
will not be possible.
*: Main heated oxygen sensor only for California specification vehicles EG±420
± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

CIRCUIT DESCRIPTION (Cont'd)
DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN
Purpose of the driving pattern.
(a) To simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded.
(b) To check that the malfunction is corrected when the repair is completed confirming that diagnostic
trouble code is no longer detected.
Malfunction: Open or Short in (Main Heated*) Oxygen Sensor
HINT: Before this test, check the feedback voltage for oxygen sensor.
(1) Disconnect the EFI No.1 fuse (30 A) for 10 sec. or more, with IG switch OFF. Initiate test
mode (Connect terminal TE2 and E1 of data link connector 2 with IG switch OFF).
(2) Start the engine and warm up.
(3) Idle the engine for 3 min.
(4) Race the engine at 2,000 rpm for 90 sec.
HINT: If a malfunction exists, the malfunction indicator lamp will light up during step (4).
NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction
will not be possible.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±429

See page
EG±421
(1) Disconnect the EFI No.1 fuse (30A) for 10 sec. or more, with IG switch OFF.
Initiate test mode (Connect terminal TE2 and E1 of data link connector 2
with IG switch OFF).
(2) Start the engine and warm up with all ACC switched OFF.
(3) Idle the engine for 5 min.
(After the engine is started, do not depress the accelerator pedal.)
(4) If the malfunction is not detected during idling, racing the engine without any load at
approx. 2,000 rpm for 60 sec.

HINT: If a malfunction exists, the malfunction indicator lamp will light up during the 5 min. idling
period or within 60 sec. of starting racing.
NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction
will not be possible.
CIRCUIT DESCRIPTION (Cont'd)
DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN
Purpose of the driving pattern.
(a) To simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded.
(b) To check that the malfunction is corrected when the repair is completed confirming that diagnostic
trouble code is no longer detected.
Malfunction: Open or Short in Injector circuit, Injector Leak or Blockage.
WIRING DIAGRAM
See page EG±421 for the WIRING DIAGRAM.
*: Only for California specification vehicles
EG±430± ENGINE2JZ±GE ENGINE TROUBLESHOOTING

CIRCUIT DESCRIPTION (Cont'd)
DIAGNOSTIC TROUBLE CODE DETECTION DRIVING PATTERN
Purpose of the driving pattern.
(a) To simulate diagnostic trouble code detecting condition after diagnostic trouble code is recorded.
(b) To check that the malfunction is corrected when the repair is completed confirming that diagnostic
trouble code is no longer detected.
(1) Disconnect the EFI No.1 fuse (30A) for 10 sec. or more, with IG switch OFF.
Initiate test mode (Connect terminal TE2 and E1 of data link connector 2 with
IG switch OFF).
(2) Start the engine and warm up with all ACC switch OFF.
(3) Deive the vehicle at 80 ~ 88 km/h (50 ~ 55 mph) for 10 min. or more.
(4) Stop at a safe place and idle the engine for 2 min. or less.
(5) Accelerate to 96 km/h (60 mph) with the throttle valve fully open.
HINT: If a malfunction exists, the malfunction indicator lamp will light up during step (5).
NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction
will not be possible.
Malfunction: Open or Short in Sub Heated Oxygen Sensor
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±435