ECO mode TOYOTA TERCEL 1996 Service Repair Manual

Important Points in the Customer Problem Analysis

What ----- Vehicle model, system name

When ----- Date, time, occurrence frequency

Where ----- Road conditions

Under what conditions? ----- Running conditions, driving conditions, weather conditions

How did it happen? ----- Problem symptoms
(Sample) Engine control system check sheet.
ENGINE CONTROL SYSTEM Check Sheet
Customer's Name
Driver's Name
Data Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading
km
miles
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Drive ability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after-fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Data Problem
ConstantSometimes ( times per day/month)
Inspector's
Name
CUSTOMER PROBLEM ANALYSIS CHECK
- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN-17
1996 TERCEL (RM440U)
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
extremely important to ask the customer about the problem and the conditions at the time it occurred.
Important Point in the Problem Analysis:
The following 5 items are important points in the problem analysis. Past problems which are thought to be
unrelated 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 troubleshooting. A customer problem analysis table is provided in Diagnostics section for each system
for your use.

DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear)Confirmation
of SymptomsDiagnostic Trouble
Code CheckProblem Condition
Diagnostic Trouble
Code DisplayProblem symptoms
existSame diagnostic
trouble code is
displayedProblem is still occurring in the diagnostic
circuit
Normal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
(The diagnostic trouble code displayed
first is either for a past problem or it is a
secondary problem)
No problem
symptoms existThe problem occurred in the diagnostic
circuit in the past
Normal Code DisplayProblem symptoms
existNormal code is
displayedThe problem is still occurring in a place
other than in the diagnostic circuit
No problem
symptoms existNormal code is
displayedThe problem occurred in a place other
than in the diagnostic circuit in the past
IN-18- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 TERCEL (RM440U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the TERCEL fulfills various functions. The first function is the Diagnostic Trouble
Code Check in which a malfunction in the signal circuits to the ECU is stored in code in the ECU memory
at the time of occurrence, to be output by the technician during troubleshooting. Another function is the Input
Signal Check which checks if the signals from various switches are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can
be performed effectively. Diagnostic functions are incorporated in the following systems in the TERCEL.
SystemDiagnostic Trouble
Code CheckInput Signal Check
(Sensor Check)Diagnostic Test
Mode (Active Test)
1. Engine
(with Check Mode)
2. Anti-Lock Brake System
3. Supplemental Restraint System
4. Power Door Lock Control System
5. Theft Deterrent System
In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the current conditions, as shown
in the table below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting
for normally operating systems, thus making it more difficult to locate the problem, or in repairs not pertinent
to the problem. Therefore, always follow the procedure in correct order and perform the diagnostic trouble
code check.

IN0CI-02
IN-36
- INTRODUCTIONTERMS
1996 TERCEL (RM440U)
GLOSSARY OF SAE AND TOYOTA TERMS
This glossary lists all SAE-J1930 terms and abbreviations used in this manual in compliance with SAE rec-
ommendations, as well as their TOYOTA equivalents.
SAE
ABBREVIATIONSSAE TERMSTOYOTA TERMS
( )--ABBREVIATIONS
A/CAir ConditioningAir Conditioner
ACLAir CleanerAir Cleaner, A/CL
AIRSecondary Air InjectionAir Injection (AI)
APAccelerator Pedal-
B+Battery Positive Voltage+B, Battery Voltage
BAROBarometric PressureHAC
CACCharge Air CoolerIntercooler
CARBCarburetorCarburetor
CFIContinuous Fuel Injection-
CKPCrankshaft PositionCrank Angle
CLClosed LoopClosed Loop
CMPCamshaft PositionCam Angle
CPPClutch Pedal Position-
CTOXContinuous Trap Oxidizer-
CTPClosed Throttle PositionLL ON, Idle ON
DFIDirect Fuel Injection (Diesel)Direct Injection (DI)
DIDistributor Ignition-
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Total Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Code
DTMDiagnostic Test Mode-
ECLEngine Control Level-
ECMEngine Control ModuleEngine ECU (Electronic Control Unit)
ECTEngine Coolant TemperatureCoolant Temperature, Water Temperature (THW)
EEPROMElectrically Erasable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
(EEPROM),
Erasable Programmable Read Only Memory (EPROM)
EFEEarly Fuel EvaporationCold Mixture Heater (CMH), Heat Control Valve (HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR)
EIElectronic IgnitionTOYOTA Distributorless Ignition (TDI)
EMEngine ModificationEngine Modification (EM)
EPROMErasable Programmable Read Only MemoryProgrammable Read Only Memory (PROM)
EVAPEvaporative EmissionEvaporative Emission Control (EVAP)
FCFan Control-
FEEPROMFlash Electrically Erasable Programmable
Read Only Memory-
FEPROMFlash Erasable Programmable Read Only Memory-
FFFlexible Fuel-
FPFuel PumpFuel Pump
GENGeneratorAlternator
GNDGroundGround (GND)

DI4LC-02
Vehicle Brought to Workshop
Customer Problem Analysis
Problem Symptom Confirmation
If the engine does not start, perform steps 10 and 12 firstConnect the OBD II scan tool or TOYOTA hand-held tester to DLC3 P. DI-3
If the display indicates a communication fault in the tool, inspect DLC3 P. DI-3
Check DTC and Freeze Frame Data (Pre-check)
Record or Print DTC and Freeze Frame Data P. DI-3
Clear DTC and Freeze Frame Data P. DI-3
Visual Inspection
Setting the Check Mode Diagnosis P. DI-3
Symptom Simulation P. IN-16
Basic Inspection P. DI-3DTC Chart P. DI-13
Matrix Chart of Problem Symptom P. DI-19
Circuit Inspection P. DI-20
Adjustment, Repair
DTC Check P. DI-3
Titles insideare titles of pages in
in the bottom portion. See the indicated
pages for detailed explanations. this manual, with the page number indicated
Malfunction
occurs.Malfunction does not occur.
Parts Inspection
Check for Intermittent Problems P. DI-3
Identification of Problem
Confirmation Test
End 1
2
3
4
5
6
7
108
9
11
12
13
15 14
16
Normal Malfunction code.
17
P. DI-2
- DIAGNOSTICSENGINE
DI-1
175 Author
: Date
:
1996 TERCEL (RM440U)
ENGINE
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following pages.

DI4LD-02
ENGINE CONTROL SYSTEM Check Sheet
Customer's Name
Driver's Name
Date Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading
km
miles
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Driveaability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after-fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Datas Problem
Occurred
Problem Frequency
Condition When
Problem Occurs
Weather
Engine Operation
Engine Temp. Place Outdoor
TemperatureConstant
Sometimes ( times per day/month)Once only
Other
Fine
CloudyRainySnowyVarious/Other
Hot
Warm CoolCold (approx. °F/ °C)
Highway
SuburbsInner CityUphillDownhill
Rough road
Other
Cold
Warming upAfter Warming upAny temp.Other
Starting
Just after starting ( min.)IdlingRacing
Driving
Constant speedAccelerationDeceleration
A/C switch ON/OFF
Other
Condition of MILRemains on Sometimes light up Does not light up
NormalMalfunction code(s) (code )
Freeze frame data ( )
NormalMalfunction code(s) (code )
Freeze frame data ( )
Normal mode
(Pre-check)
Check Mode DTC InspectionInspector's
Name
DI-2
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
CUSTOMER PROBLEM ANALYSIS CHECK

N09214
DTC3 DI-4
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)

The diagnosis system operates in normal mode
during normal vehicle use. It also has a check mode
for technicians to simulate malfunction symptoms
and troubleshoot. Most DTC use 2 trip detection
logic* to prevent erroneous detection, and ensure
thorough malfunction detection. By switching the
ECM to check mode when troubleshooting, the
technician can cause the MIL to light up for a mal-
function that is only detected once or momentarily
(TOYOTA hand-held tester only) (See page
DI-3).

*2 trip detection logic:
When a logic malfunction is first detected, the mal-
function is temporarily stored in the ECM memory.
If the same malfunction is detected again during the
second drive test, this second detection causes the
MIL to light up.

The 2 trip repeats the same mode a 2nd time (How-
ever, the IG switch must be turned OFF between the
1st trip and 2nd trip.).

Freeze frame data:
Freeze frame data records the engine condition
when a misfire (DTC P0300 - P0304) or fuel trim
malfunction (DTC P0171, P0172) or other malfunc-
tion (first malfunction only), is detected, as freeze
frame data records the engine conditions (fuel sys-
tem, calculator load, engine coolant temperature,
fuel trim,engine speed, vehicle speed, etc.) when
the malfunction is detected, when troubleshooting
it is useful for determining whether the vehicle was
running or stopped, the engine warmed up or not,
the air-fuel ratio lean or rich, etc. at the time of the
malfunction.
Priorities for troubleshooting:
If troubleshooting priorities for multiple DTC are given in the ap-
plicable DTC chart, these should be followed.
If no instructions are given troubleshoot DTC according to the
following priorities.
(1) DTC other than fuel trim malfunction (DTC P0171,
P0172) and misfire (DTC P0300 - P0304).
(2) Fuel trim malfunction (DTC P0171, P0172).
(3) Misfire (DTC P0300 - P0304).
(b) Check the DLC3.
The vehicle's ECM uses ISO 9141-2 for communication.
The terminal arrangement of DLC3 complies with SAE
J1962 and matches the ISO 9141-2 format.

S00840
- DIAGNOSTICSENGINE
DI-5
1996 TERCEL (RM440U)Terminal No.
Connection / Voltage or ResistanceCondition
7Bus + Line / Pulse generationDuring transmission
4Chassis Ground - Body Ground / 1 W or lessAlways
5Signal Ground - Body Ground / 1 W or lessAlways
16Battery Positive - Body Ground / 9 - 14 VAlways
HINT:
If your display shows ºUNABLE TO CONNECT TO VEHICLEº
when you have connected the cable of the OBD II scan tool or
TOYOTA hand-held tester to DLC3, turned the ignition switch
ON and operated the scan tool, there is a problem on the ve-
hicle side or tool side.

If communication is normal when the tool is connected to
another vehicle, inspect DLC3 on the original vehicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tool its self, so consult the Service Department listed in
the tool's instruction manual.
2. Normal Mode:
INSPECT DIAGNOSIS
(a) Check the MIL.
(1) The MIL comes on when the ignition switch is turned
ON and the engine is not running.
HINT:
If the MIL does not light up, troubleshoot the combination meter.
(2) When the engine started, the MIL should go off. If
the lamp remains on, the diagnosis system has de-
tected a malfunction or abnormality in the system
(b) Check the DTC.
NOTICE:
TOYOTA hand-held tester only: When the diagnosis sys-
tem is switched from the normal mode to the check mode,
it erases all DTC and freeze frame data recorded in the nor-
mal mode. So before switching modes, always check the
DTC and freeze frame data, and note them down.
(1) Prepare the OBD II scan tool (complying with SAE
J 1978) or TOYOTA hand-held tester.
(2) Connect the OBD II scan tool or TOYOTA hand-
held tester to DLC3 in the fuse box at the lower left
of the instrument panel.
(3) Turn the ignition switch ON and turn the OBD II scan
tool or TOYOTA hand-held tester switch ON.
(4) Use the OBD II scan tool or TOYOTA hand-held
tester to check the DTC and freezed frame data;
note them down (For operating instructions, see the
OBD II scan tool's instruction book.).
(5) See page DI-13 to confirm the details of the
DTC.

FI3605
Flashing
ON
OFF
0.13 Seconds
DI-6
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
NOTICE:
When simulating symptoms with an OBD II scan tool (ex-
cluding TOYOTA hand-held tester) to check the DTC, use
the normal mode. For code on the DTC chart subject to º2
trip detection logicº, turn the ignition switch OFF after the
symptom is simulated the first time. Then repeat the simu-
lation process again. When the problem has been simu-
lated twice, the MIL lights up and the DTC are recorded in
the ECM.
3. Check Mode:
INSPECT DIAGNOSIS
HINT:
TOYOTA hand-held tester only:
Compared to the normal mode, the check mode has an in-
creased sensitivity to detect malfunctions.
Furthermore, the same diagnostic items which are detected in
the normal mode can also be detected in the check mode.
(a) Check the DTC.
(1) Initial conditions.

Battery positive voltage 11V or more.

Throttle valve fully closed.

Transmission in ºPº or ºNº position.

Air conditioning switched OFF.
(2) Turn the ignition switch OFF.
(3) Prepare the TOYOTA hand-held tester.
(4) Connect the TOYOTA hand-held tester to DLC3 in
the fuse box at the lower left of the instrument panel.
(5) Turn the ignition switch ON and switch the TOYOTA
hand-held tester ON.
(6) Switch the TOYOTA hand-held tester normal mode
to check mode. (Check that the MIL flashes.)
(7) Switch the engine. (The MIL goes out after the en-
gine start.)
(8) Simulate the conditions of the malfunction de-
scribed by the customer.
NOTICE:
Leave the ignition switch ON until you have checked the
DTC, etc.
(9) After simulating the malfunction conditions, use the
TOYOTA hand-held tester diagnosis selector to
check the DTC and freezed frame data, etc.
HINT:
Take care not to turn the ignition switch OFF. Turning the ignition
switch OFF switches the diagnosis system from check mode to
normal mode, so all DTC, etc. are erased.
(10) After checking the DTC, inspect the applicable cir-
cuit.

- DIAGNOSTICSENGINE
DI-7
1996 TERCEL (RM440U)
(b) Clear the DTC.
The following actions will erase the DTC and freezed
frame data.
(1) Operating the OBD II scan tool (complying with SAE
J1978) or TOYOTA hand-held tester to erase the
codes. (See the OBD II scan tool's instruction book
for operating instructions.)
(2) Disconnecting the battery terminals or EFI fuse.
NOTICE:
If the TOYOTA hand-held tester switches the ECM from
normal mode to check mode or vice-versa, or if the igni-
tion switch is turned from ON to ACC or OFF during check
mode, the DTC and freezed frame data will be erased.
4. FAIL-SAFE CHART
If any of the following codes is recorded, the ECM enters fail-safe mode.
DTC No.Fail-Safe OperationFail-Safe Deactivation Conditions
P0105Ignition timing fixed at 5° BTDCReturned to normal condition
P0110Intake air temp. is fixed at 20°C (68°F)Returned to normal condition
P0115Engine coolant temp. is fixed at 80°C (176°F)Returned to normal condition
P0120VTA is fixed at 0°
The following condition must be repeated at least 2 times
consecutively
When closed throttle position switch is ON:
0.1 V
VTA
0.95 V
P0141The heater circuit in which an abnormality is detected is
turned offIgnition switch OFF
P0325Max. timing retardationIgnition switch OFF
P1300Fuel cutIGF signal is detected for 4 consecutive ignitions
5. CHECK FOR INTERMITTENT PROBLEMS
HINT:
TOYOTA hand-held tester only:
By putting the vehicle's ECM in check mode, 1 trip detection logic is possible instead of 2 trip detection logic
and sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
(a) Clear the DTC (See page DI-13).
(b) Set the check mode (See page DI-13).
(c) Perform a simulation test (See page IN-26).
(d) Check the connector and terminal (See page IN-26).
(e) Handle the connector (See page IN-26).
6. BASIC INSPECTION
When the malfunction code is not confirmed in the DTC check, troubleshooting should be performed in the
order for all possible circuits to be considered as the causes of the problems. In many cases, by carrying
out the basic engine check shown in the following flow chart, the location causing the problem can be found
quickly and efficiently. Therefore, use of this check is essential in engine troubleshooting.
1 Is battery positive voltage 11V or more when engine is stopped ?
NO Charge or replace battery.

P25916
S00553
DI-10
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
7 Check fuel pressure.
PREPARATION:
(a) Be sure that enough fuel is in the tank.
(b) Turn ignition switch ON.
(c) Remove the fuse cover on the instrument panel.
(d) Connect the TOYOTA hand-held tester to DLC3 on the
vehicle.
(e) Use ACTIVE TEST mode to operate the fuel pump.
(f) If you have no TOYOTA hand-held tester, connect the
positive (+) and negative (-) leads from the battery to the
fuel pump connector (See page MF-1).
CHECK:
Check for fuel pressure in the inlet hose when it is pinched off.
HINT:
At this time, you will hear a fuel flowing noise.
NG Proceed to page MF-1 and continue to trouble-
shoot.
OK
8 Check for spark.
PREPARATION:
(a) Disconnect the high-tension cord from spark plug or re-
move the ignition coil.
(b) Remove spark plug.
(c) Install the spark plug to high-tension cord or ignition coil.
(d) Disconnect injector connector.
(e) Ground the spark plug.
CHECK:
Check if spark occurs while engine is being cranked.
NOTICE:
To prevent excess fuel being injected from the injectors
during this test, do not crank the engine for more than 5 -
10 seconds at a time.
NG Proceed to page IG-1 and continue to trouble-
shoot.
OK