1996 TOYOTA TERCEL check engine

A15742
A15683
- DIAGNOSTICSENGINE
DI-27
1996 TERCEL (RM440U)
4 Check for short in harness and ECM.
PREPARATION:
(a) Disconnect the intake air temp. sensor connector.
(b) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: -40°C (-40°F)
OK Replace intake air temp. sensor.
NG
5 Check for short in harness or ECM.
PREPARATION:
(a) Remove the lower finish panel.
(b) Disconnect the E7 connector of ECM.
HINT:
Intake air temperature sensor connector is disconnected.
(c) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: -40°C (-40°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM (See page IN-26).

A15685
- DIAGNOSTICSENGINE
DI-29
1996 TERCEL (RM440U)
INSPECTION PROCEDURE
HINT:
If DTC P0105, P0106, 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 engine
coolant temperature.
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 OBD II scan tool or TOYOTA hand-held tester main switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA hand-held tester.
OK:
Same value as the actual engine coolant temperature
HINT:

If there is open circuit, OBD II scan tool or TOYOTA hand-held tester indicates -40°C (-40°F).

If there is short circuit, OBD II scan tool or TOYOTA hand-held tester indicates 140°C (284°F) or more.
NG -40°C (-40°F) ... Go to step 2.
140°C (284°F) or more ... Go to step 4.
OK
Check for intermittent problems (See page
DI-3).
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Connect sensor wire harness terminals together.
(c) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: 140°C (284°F) or more
OK Confirm good connection at sensor. If OK, re-
place engine coolant temp. sensor
NG

A15686
A15687
DI-30
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
3 Check for open in harness or ECM.
PREPARATION:
(a) Remove the lower finish panel.
(b) Connect terminals THW and E2 of ECM connector to-
gether.
HINT:
Engine coolant temperature sensor connector is disconnected.
Before checking, do a visual and contact pressure check for the
ECM connector (See page IN-26).
(c) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: 140°C (284°F) or more
OK Open in harness between terminal E2 or termi-
nal THW, repair or replace harness.
NG
Confirm good connection at ECM.
If OK, replace ECM.
4 Check for short in harness and ECM.
PREPARATION:
(a) Disconnect the engine coolant temperature sensor con-
nector.
(b) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: -40°C (-40°F)
OK Replace engine coolant temperature sensor.
NG

A15688
- DIAGNOSTICSENGINE
DI-31
1996 TERCEL (RM440U)
5 Check for short in harness or ECM.
PREPARATION:
(a) Remove the lower finish panel.
(b) Disconnect the E7 connector of ECM.
HINT:
The engine coolant temperature sensor connector is discon-
nected.
(c) Turn the ignition switch ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYO-
TA hand-held tester.
OK:
Temperature value: -40°C (-40°F)
OK Repair or replace harness or connector.
NG
Check and replace ECM (See page IN-26).

DI-32
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
DTC P0116 Engine Coolant Temp. Circuit Range/
Performance Problem
CIRCUIT DESCRIPTION
Refer to Engine Coolant Temp. Circuit Malfunction on page DI-28.
DTC No.DTC Detection ConditionTrouble Area
P0116
20 min. or more after the engine starts, engine coolant
temp. sensor value is 40°C (104°F) or less (2 trip detection
logic)
Engine coolant temp. sensor

Cooling system
INSPECTION PROCEDURE
HINT:
If DTC P0115 and P0116 are output Simultaneously, engine coolant temperature sensor circuit may be open.
Perform troubleshooting of DTC P0115 first.
1 Are there any other codes (besides DTC P0116) being output?
YES Go to relevant DTC chart.
NO
2 Check thermostat (See page CO-10).
NG Replace thermostat.
OK
Replace engine coolant temp. sensor.
DI1E7-08

A15689
FI7052
DI-34
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTC P0105, P0110, P0120 are output simultaneously, E2 (sensor ground) may be open.
1 Connect OBD II scan tool or TOYOTA hand-held tester and read throttle valve
opening percentage.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the OBD II scan tool or TOYOTA hand-held tes-
ter to the DLC3.
(c) Turn the ignition switch ON and OBD II scan tool or TOY-
OTA hand-held tester main switch ON.
CHECK:
Read the throttle valve opening percentage.
OK:
Throttle valveThrottle valve opening
position expressed as percentage
Fully openApprox. 70 %
Fully closedApprox. 10 %
OK Check for intermittent problems
(See page DI-3).
NG

A00369
1 (+) ON
S03529 BE6653A00854
ON
VTA (+) E2 (-)
- DIAGNOSTICSENGINE
DI-35
1996 TERCEL (RM440U)
2 Check voltage between terminal 1 of wire harness side connector and body
ground.
PREPARATION:
(a) Disconnect the throttle position sensor connector.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminal 1 of wire harness side
connector and the body ground.
OK:
Voltage: 4.5 - 5.5 V
NG Go to step 5.
OK
3 Check throttle position sensor (See page MF-26).
NG Replace throttle position sensor.
OK
4 Check voltage between terminals VTA and E2 of ECM connector.
PREPARATION:
(a) Remove the lower finish panel.
(b) Turn the ignition switch ON.
CHECK:
Measure the voltage between terminals VTA and E2 of the ECM
connector.
OK:
Throttle ValveVoltage
Fully closed0.3 - 1.0 V
Fully open3.2 - 4.9 V
NG Check for open and short in harness and con-
nector between ECM and throttle position sen-
sor (VTA or E2 line) (See page IN-26).
OK

BE6653S03524A03999
ON
VC (+) E2 (-)
DI-36
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
Check and replace ECM (See page IN-26).
5 Check voltage between terminals VC and E2 of ECM connector.
PREPARATION:
(a) Remove the lower center 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
Check for open in harness and connector
between ECM and sensor (VC line)
(See page IN-26).