ECM TOYOTA TERCEL 1996 Service Manual PDF

A15717
- DIAGNOSTICSENGINE
DI-81
1996 TERCEL (RM440U)
DTC P0510 Closed Throttle Position Switch Malfunction
CIRCUIT DESCRIPTION
Refer to DTC P0120 on page DI-33.
DTC No.DTC Detection ConditionTrouble Area
P0510Closed throttle position switch does not turn ON even once
when vehicle is driven (2 trip detection logic)
Open in closed throttle position switch circuit

Closed throttle position switch

ECM
HINT:
After confirming DTC P0510, use the TOYOTA hand-held tester to confirm the closed throttle position switch
signal from the CURRENT DATA.
Throttle ValveClosed Throttle Position Switch SignalMalfunction
Fully closedOFFOpen circuit
Fully openONShort circuit
WIRING DIAGRAM
Refer to DTC P0120 on page DI-33.
INSPECTION PROCEDURE
HINT:
If DTCs P0110, P0115 and P0120 are output simultaneously, E2 (sensor ground) may be open.
TOYOTA hand-held tester:
1 Check for open in harness or ECM.
PREPARATION:
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Disconnect the throttle position sensor connector.
(c) Connect the sensor wire harness terminals between ter-
minals 3 and 4.
(d) Turn the ignition switch ON.
CHECK:
Read thg CTP switch signal on the TOYOTA hand-held tester.
OK:
CTP switch signal: ON
OK Confirm good connection at sensor. If OK, re-
place throttle position sensor.
NG
DI95R-01

A15718
A15719
DI-82
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
2 Check for open in harness or ECM.
PREPARATION:
(a) Remove the glove compartment (See page MF-54).
(b) Connect terminals IDL and E2 of the ECM connector to-
gether.
HINT:
The throttle position sensor connector is disconnected. Before
checking, do a visual check and contact pressure check for the
connector (See page IN-26).
(c) Turn the ignition switch ON.
CHECK:
Read the CTP switch signal on the TOYOTA hand-held tester.
OK:
CTP switch signal: ON
OK Open in harness between ECM and throttle
position sensor, repair or replace harness.
NG
Confirm connection at ECM. If OK, replace
ECM.
OBD II scan tool (excluding TOYOTA hand-held tester):
1 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect the throttle position sensor connector.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals 3 and 4 of the throttle
position sensor connector.
OK:
Voltage: 9 - 14 V
OK Confirm good connection at sensor. If OK, re-
place throttle position sensor.

- DIAGNOSTICSENGINE
DI-83
1996 TERCEL (RM440U)
NG
2 Check for open in harness and connector between throttle position sensor and
ECM (See page IN-26).
NG Open in harness between ECM and throttle
position sensor.
OK
Confirm connection at ECM. If OK, replace
ECM.

S00591
From Battery
Ignition Coil
Spark Plug
IGC1
IGC2
GND TA C IGT1
IGT2
To Tachometer ECM G
NE
No.1 Cylinder
No.4 Cylinder
Various
Sensor
IGF
No.2 Cylinder
No.3 Cylinder Camshaft
Position
Sensor
Crankshaft
Position
SensorIgniter
DI-84
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
DTC P1300 Ignition Circuit Malfunction
CIRCUIT DESCRIPTION
A DIS (Direct Ignition System) has been adopted. The DIS improves the ignition timing accuracy, reduces
high-voltage loss, and enhances the overall reliability of the ignition system by eliminating the distributor.
The DIS is a 2-cylinder simultaneous ignition system which ignites 2 cylinders simultaneously with one igni-
tion coil. In the 2-cylinder simultaneous ignition system, each of the 2 spark plugs is connected to the end
of the secondary winding. High voltage generated in the secondary winding is applied directly to the 2 spark
plugs. The sparks of the 2 spark plugs pass simultaneously from the center electrode to the ground elec-
trode.
The ECM determines ignition timing end outputs the ignition signals (IGT) for each cylinder. Based on IGT
signals, the igniter controls the primary ignition signals (IGC) for all ignition coils. At the same time, the igniter
also sends an ignition confirmation signal (IGF) as a fail-safe measure to the ECM.
DTC No.DTC Detection ConditionTrouble Area
P1300No IGF signal to ECM while engine is running

Open or short in IGF or IGT circuit from igniter to ECM

Igniter

ECM
DI3A0-04

A15721
- DIAGNOSTICSENGINE
DI-85
1996 TERCEL (RM440U)
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check spark plug and spark (See page IG-1).
NG Go to step 4.
OK
2 Check for open and short in harness and connector in IGF signal circuit between
ECM and igniter (See page IN-26).
NG Repair or replace harness or connector.

A15722
A15723
DI-86
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
OK
3 Disconnect igniter connector and check voltage between terminal IGF of ECM
connector and body ground.
PREPARATION:
(a) Disconnect the igniter connector.
(b) Remove the lower finish panel.
(c) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal IGF of the ECM connec-
tor and the body ground.
OK:
Voltage: 4.5 - 5.5 V
OK Replace igniter.
NG
Check and replace ECM (See page IN-26).
4 Check for open and short in harness and connector in IGT1 and IGT2 signal cir-
cuits between ECM and igniter (See page IN-26).
NG Repair or replace harness or connector.
OK
5 Check voltage between terminals IGT1 and IGT2 of ECM connector and body
ground.
PREPARATION:
Remove the lower finish panel.
CHECK:
Measure the voltage between terminals IGT1 and IGT2 of the
ECM connector and the body ground when the engine is
cranked.
OK:
Voltage: More than 0.1 V and less than 4.5 V

P19902
IGT1 / IGF signal waveform
10 m sec./Division (Idling) IGT12V/
Division
IGF
A15725
A15726
- DIAGNOSTICSENGINE
DI-87
1996 TERCEL (RM440U)
Reference: INSPECTION USING OSCILLOSCOPE
During idling, check waveform between terminals IGT1 and E1
of ECM.
HINT:
The correct waveform are as shown.
IGT2 signal waveform is same as the IGT1 signal waveform.
NG Check and replace ECM (See page IN-26).
OK
6 Disconnect igniter connector and check voltage between terminals IGT1 and
IGT2 of ECM connector and body ground.
PREPARATION:
(a) Disconnect the igniter connector.
(b) Remove the lower finish panel.
CHECK:
Measure the voltage between terminals IGT1 and IGT2 of the
ECM connector and the body ground when the engine is
cranked.
OK:
Voltage: More than 0.1 V and less than 4.5 V
NG Check and replace ECM (See page IN-26).
OK
7 Check voltage between terminal 7 of igniter connector and body ground.
PREPARATION:
Disconnect the igniter connector.
CHECK:
Measure the voltage between terminal 7 of igniter connector
and the body ground, when ignition switch is turned to ON and
START position.
OK:
Voltage: 9 - 14 V
NG Check and repair igniter power source circuit.
OK

- DIAGNOSTICSENGINE
DI-89
1996 TERCEL (RM440U)
DTC P1335 Crankshaft Position Sensor Circuit
Malfunction (During engine running)
CIRCUIT DESCRIPTION
Refer to DTC P0335 on page DI-60.
DTC No.DTC Detection ConditionTrouble Area
P1335No crankshaft position sensor signal to ECM with engine
speed 1,000 rpm or more
Open or short in crankshaft position sensor circuit

Crankshaft position sensor

ECM
WIRING DIAGRAM
Refer to DTC P0335 on page DI-60.
DI1EH-14

A15727
DI-90
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
DTC P1500 Starter Signal Circuit Malfunction
CIRCUIT DESCRIPTION
When the engine is cranked, the intake air flow is slow, so fuel vaporization is poor. A rich mixture is therefore
necessary in order to achieve good startability. While the engine is being cranked, the battery voltage is ap-
plied to terminal STA of the ECM. The starter signal is mainly used to increase the fuel injection volume for
the starting injection control and after-start injection control.
DTC No.DTC Detection ConditionTrouble Area
P1500No starter signal to ECM

Open or short in starter signal circuit

Open or short in ignition switch or starter relay circuit

ECM
HINT:
In this circuit, diagnosis can only be made in the check mode.
WIRING DIAGRAM
DI95S-01

- DIAGNOSTICSENGINE
DI-91
1996 TERCEL (RM440U)
INSPECTION PROCEDURE
HINT:
This diagnostic chart is based on the premise that the engine is cranked normally. If the engine is not
cranked, proceed to the problem symptoms table on page DI-19.
1 Connect TOYOTA hand-held tester, and check STA signal.
PREPARATION:
(a) Connect the TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
CHECK:
Read the STA signal on the TOYOTA hand-held tester while the starter operates.
OK:
Ignition Switch PositionONSTART
STA SignalOFFON
OK Proceed to next circuit inspection shown on
problem symptoms table (See page DI-19).
NG
2 Check for open in harness and connector between ECM and starter relay (See
page IN-26).
NG Repair or replace or connector.
OK
Check and replace ECM.