check engine TOYOTA TERCEL 1996 Service Owner's Manual

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.

MA0659
Outside
Inside
DI-8
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
YES
2 Is engine cranked ?
NO Proceed to ST-13, ST-28, ST-31 and continue
to troubleshoot.
YES
3 Does engine start ?
NO Go to step 7.
YES
4 Check air filter.
PREPARATION:
Remove the air filter.
CHECK:
Visual check that the air cleaner element is not excessively dirty
or oily.
HINT:
If necessary, clean the filter with compressed air. First blow from
inside thoroughly, then blow from outside of filter.
NG Repair or replace.
OK
5 Check engine idle speed.
PREPARATION:
(a) Warm up engine to normal operating temperature.
(b) Switch off all accessories.
(c) Switch off air conditioning.
(d) Shift transmission into ºNº position.

P25914P25915A07081
TE1
E1 SST
DLC1
- DIAGNOSTICSENGINE
DI-9
1996 TERCEL (RM440U)
(e) Remove the fuse cover on the instrument panel.
(f) Connect the OBD II scan tool or TOYOTA hand-held tester to DLC3 on the vehicle.
CHECK:
Use CURRENT DATA to check the engine idle speed.
OK:
Idle speed: 700 - 800 rpm
NG Proceed to matrix chart of problem symptoms
on page DI-19.
OK
6 Check ignition timing.
PREPARATION:
(a) Warm up engine to normal operating temperature.
(b) Shift transmission into ºNº position.
(c) Keep the engine speed at idle.
(d) Using SST, connect terminals TE1 and E1 of DLC1.
SST 09843-18020
(e) Using a timing light, connect the tester to No.1 high-ten-
sion cord.
CHECK:
Check ignition timing.
OK:
Ignition timing: 10° BTDC at idle
NG Proceed to page IG-1 and continue to trouble-
shoot.
OK
Proceed to matrix chart of problem symp-
toms on page DI-19.

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

DI4LF-02
- DIAGNOSTICSENGINE
DI-13
1996 TERCEL (RM440U)
DIAGNOSTIC TROUBLE CODE CHART
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument
or other factors.
If a malfunction code is displayed during the DTC check in check mode, check the circuit for that code listed
in the table below, for details of each code, turn to the page referred to under the ''See page '' for the respec-
tive ''DTC No.'' in the DTC chart.
SAE Controlled:
DTC No.
(See Page)Detection ItemTrouble AreaMIL*Memory
P0105
(DI-20)
Manifold Absolute
Pressure/Barometric
Pressure Circuit
MalfunctionOpen or short in manifold absolute pressure sensor circuit
Manifold absolute pressure sensor
ECM

P0106
(DI-23)
Manifold Absolute
Pressure/Barometric
Pressure Circuit
Range/Performance Problem
Manifold absolute pressure sensor
P0110
(DI-24)Intake Air Temp. Circuit
MalfunctionOpen or short in intake air temp. sensor circuit
Intake air temp. sensor
ECM

P0115
(DI-28)Engine Coolant Temp. Circuit
MalfunctionOpen or short in engine coolant temp. sensor circuit
Engine coolant temp. sensor
ECM

P0116
(DI-32)Engine Coolant Temp. Circuit
Range/Performance ProblemEngine coolant temp. sensor
Cooling system
P0120
(DI-33)Throttle/Pedal Position
Sensor/Switch ºAº Circuit
MalfunctionOpen or short in throttle position sensor circuit
Throttle position sensor
ECM

P0121
(DI-37)Throttle/Pedal Position
Sensor/Switch ºAº Circuit
Range/Performance Problem
Throttle position sensor
P0125
(DI-38)Insufficient Coolant Temp. for
Closed Loop Fuel ControlOpen or short in oxygen sensor circuit
Oxygen sensor
P0130
(DI-41)Oxygen Sensor Circuit
Malfunction (Bank 1 Sensor 1)Heated oxygen sensor
Fuel trim malfunction
P0133
(DI-44)Oxygen Sensor Circuit
Slow Response
(Bank 1 Sensor 1)
Oxygen sensor
P0136
(DI-45)Heated Oxygen Sensor Circuit
Malfunction
(Bank 1 Sensor 2)
Heated oxygen sensor
P0141
(DI-47) Heated Oxygen Sensor Heater
Circuit Malfunction
(Bank 1 Sensor 2)Open or short in heater circuit of heated oxygen sensor
Heated oxygen sensor heater
ECM

*: 


MIL lights up

A15677
- DIAGNOSTICSENGINE
DI-21
1996 TERCEL (RM440U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTC P0105, P0110, P0115, P0120 are output simultaneously, E2 (sensor ground) may be open.
1 Connect OBD II scan tool or TOYOTA hand-held tester, and read value of man-
ifold absolute pressure.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(c) Turn the ignition switch ON and OBDII scan tool or TOYOTA hand-held tester main switch ON.
CHECK:
Read value of manifold absolute pressure on the OBD II scan tool or TOYOTA hand-held tester.
OK:
Same value as the atmospheric pressure
OK Check for intermittent problems (See page
DI-3).
NG

A15678
A15679
DI-22
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
2 Check voltage between terminals VC and E2 of ECM connector.
PREPARATION:
(a) Remove the lower finish panel.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals VC and E2 of the ECM
connector.
OK:
Voltage: 4.5 - 5.5 V
NG Check and replace ECM (See page IN-26).
OK
3 Check voltage between terminals PIM and E2 of ECM connector.
PREPARATION:
(a) Remove the lower finish panel.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals PIM and E2 of ECM con-
nector.
OK:
Voltage: 3.3 - 3.9 V
OK Check and replace ECM (See page IN-26).
NG
4 Check for open and short in harness and connector between manifold absolute
pressure sensor and ECM.
NG Repair or replace harness or connector.
OK
Replace manifold absolute pressure sensor.

- DIAGNOSTICSENGINE
DI-23
1996 TERCEL (RM440U)
DTC P0106 Manifold Absolute Pressure/Barometric
Presure Circuit Range/Performance Problem
CIRCUIT DESCRIPTION
Refer to DTC P0105 on page DI-20.
DTC No.DTC Detection ConditionTrouble Area
P0106
Conditions (a) and (b) continue with engine speed
400 - 1,000 rpm:
(2 trip detection logic)
(a) Closed throttle position switch: ON
(b) Manifold absolute pressure sensor output > 3.0 V

Manifold absolute pressure sensor
WIRING DIAGRAM
Refer to DTC P0105 on page DI-20.
INSPECTION PROCEDURE
HINT:
If DTC P0105 and P0106 are output simultaneously, manifold absolute pressure sensor circuit may be open.
Perform troubleshooting of DTC P0105 first.
1 Are there any other codes (besides DTC P0106) being output?
YES Go to relevant DTC chart.
NO
2 Check manifold absolute pressure sensor (See page MF-48).
NG Replace manifold absolute pressure sensor.
OK
Check vacuum line for manifold absolute
pressure sensor for blockage.
DI1E4-05