1996 TOYOTA TERCEL engine coolant

- DIAGNOSTICSENGINE
DI-1 1
1996 TERCEL (RM440U)
Proceed to matrix chart of problem symp-
toms on page DI-19.
7. ENGINE OPERATING CONDITION
NOTICE:
The values given below for ºNormal Conditionº are representative values, so a vehicle may still be
normal even if its value from those listed here. So do not decide whether a part is faulty or not solely
according to the ºNormal Conditionº here.
CARB mandated signals:
TOYOTA hand-held tester displayMeasurement ItemNormal Condition*
FUEL SYS #1
Fuel System Bank 1
OPEN: Air-fuel ratio feedback stopped
CLOSED: Air-fuel ratio feedback operating
Idling after warming up: CLOSED
CALC LOAD
Calculator Load:
Current intake air volume as a proportion of max.
intake air volumeIdling: 19.7 - 47.4 %
Racing without load (2,500rpm): 18.8 - 46.4 %
COOLANT TEMP.Engine Coolant Temp. Sensor ValueAfter warming up: 80 - 95°C (176 - 203°F)
SHORT FT #1Short-term Fuel Trim Bank 10 ± 20%
LONG FT #1Long-term Fuel Trim Bank 10 ± 20%
ENGINE SPDEngine SpeedIdling: 700 - 800 rpm
VEHICLE SPDVehicle SpeedVehicle Stopped: 0 km/h (0 mph)
IGN ADVANCEIgnition Advance:
Ignition Timing of Cylinder No. 1Idling: BTDC 7 - 14°
INTAKE AIRIntake Air Temp. Sensor ValueEquivalent to Ambient Temp.
MAPAbsolute Pressure Inside Intake Manifold
Idling: 20 - 48 kPa
Racing without load (2,500 rpm):
19 - 47 kPa
THROTTLE POS
Voltage Output of Throttle Position Sensor
Calculated as a percentage:
0 V "0%, 5 V "100%Throttle Fully Closed: 6 - 16 %
Throttle Fully Open: 64 - 98 %
O2S B1, S1Voltage Output of Heated Oxygen Sensor
Bank 1, Sensor 1Idling: 0.1 - 0.9 V
O2FT B1, S1Oxygen Sensor Fuel Trim Bank 1, Sensor 1
(Same as SHORT FT #1)0 ± 20 %
O2S B1, S2Voltage Output of Oxygen Sensor
Bank 1, Sensor 2Driving at 50 km/h (31 mph): 0.1 - 0.9 V
*: If no conditions are specifically stated for ºldlingº, it means the shift lever is at N or P position, the A/C switch
is OFF and all accessory switches are OFF.

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

DI-14
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)DTC No.
(See Page)
Detection ItemTrouble AreaMIL*Memory
P0171
(DI-49)System too Lean
(Fuel Trim)
Air intake (hose loose)
Fuel line pressure
Injector blockage
Oxygen sensor malfunction
Manifold absolute pressure sensor
Engine coolant temp. sensor

P0172
(DI-49)System too Rich
(Fuel Trim)
Fuel line pressure
Injector blockage, leak
Oxygen sensor malfunction
Manifold absolute pressure sensor
Engine coolant temp. sensor

P0300
(DI-52)Random/Multiple Cylinder
Misfire DetectedIgnition system
Injector
FlliP0301
P0302
P0303
P0304
(DI-52)Misfire Detected
- Cylinder 1
- Cylinder 2
- Cylinder 3
- Cylinder 4Fuel line pressure
Compression pressure
Valve clearance not to specification
Valve timing
Manifold absolute pressure sensor
Engine coolant temp. sensor

P0325
(DI-57)Knock Sensor 1 Circuit
MalfunctionOpen or short in knock sensor 1 circuit
Knock sensor 1 (looseness)
ECM

P0335
(DI-60)Crankshaft Position Sensor
Circuit ºAº Malfunction
Open or short in crankshaft position sensor circuit
Crankshaft position sensor
Starter
ECM

P0340
(DI-63)Camshaft Position Sensor
Circuit Malfunction
Open or short in camshaft position sensor circuit
Camshaft position sensor
Starter
ECM

P0420
(DI-73)Catalyst System Efficiency
Below ThresholdThree-way catalytic converter
Open or short in (heated) oxygen sensor circuit
(Heated) oxygen sensor

P0500
(DI-76)Vehicle Speed Sensor
Malfunction
Open or short in vehicle speed sensor circuit
Vehicle speed sensor
Speedometer cable
ECM

P0505
(DI-78)Idle Control System
Malfunction
IAC valve is stuck or closed
Open or short in IAC valve circuit
Open or short in AC1 switch circuit
Air intake (hose loose)

*: 


MIL lights up

DI4LH-02
P19551
ECM TerminalsE7 E6
1 2 3 4 5 6 7 8 9 10 11 12 13
23 24 25 26 1920 21 22 18 1415 16 171 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16
- DIAGNOSTICSENGINE
DI-17
1996 TERCEL (RM440U)
TERMINALS OF ECM
Symbols (Terminals No.)Wiring ColorConditionSTD Voltage (V)
BATT (E6-2) - E1 (E7-24)W-R - BRAlways9 - 14
+B (E6-9) - E1 (E7-24)B-R - BRIG switch ON9 - 14
VC (E7-18) - E2 (E7-16)LG-R - BRIG switch ON4.5 - 5.5
VTA (E7 19) E2 (E7 16)YG BR
IG switch ON
Throttle valve fully closed0.3 - 1.0
VTA (E7-19) - E2 (E7-16)Y-G - BRIG switch ON
Throttle valve fully open3.2 - 4.9
PIM (E7 4) E2 (E7 16)PBRIG switch ON3.3 - 3.9PIM (E7-4) - E2 (E7-16)P - BRApply vacuum 26.7 kPa (200 mmHg, 7.9 in.Hg)2.5 - 3.1
THA (E7-15) - E2 (E7-16)L-B - BRIdling, Intake air temp. 20°C (68° F)0.5 - 3.4
THW (E7-3) - E2 (E7-16)G-B - BRIdling, Engine coolant temp. 80°C (176°F) 0.2 - 1.0
STA (E7-11) - E1 (E7-24)B-W - BRCranking6.0 or more
IG switch ON9 - 14
#10 (E7-12) - E01 (E7-13)G - BRIdlingPulse generation
(See page DI-52)
IG switch ON9 - 14
#20 (E7-11) - E01 (E7-13)Y - BRIdlingPulse generation
(See page DI-52)
IG switch ON9 - 14
#30 (E7-25) - E01 (E7-13)R - BRIdlingPulse generation
(See page DI-52)
IG switch ON9 - 14
#40 (E7-24) - E01 (E7-13)L - BRIdlingPulse generation
(See page DI-52)
IGT1 (E7-6) - E1 (E7-24)LG - BRIdlingPulse generation
(See page DI-84)
IGT2 (E7-5) - E1 (E7-24)L-Y - BRIdlingPulse generation
(See page DI-84)
IG switch ON, Disconnect igniter connector4.5 - 5.5
IGF (E7-7) - E1 (E7-24)LG-B - BRIdlingPulse generation
(See page DI-84)
G2(E7-20) - NE- (E7-9)R - WIdlingPulse generation
(See page DI-60)
NE(E7-21) - NE- (E7-9)B - WIdlingPulse generation
(See page DI-60)
FC (E6-4) - E1 (E7-24)G-B - BRIG switch ON9 - 14

A10940
ECM
E7
E7 G-B
BR5V
E1 E2 THW
2
1 Engine Coolant Temp. Sensor
3
16 DI-28
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
DTC P0115 Engine Coolant Temp. Circuit Malfunction
CIRCUIT DESCRIPTION
A thermistor built into the engine coolant temperature sensor changes the resistance value according to the
engine coolant temperature. The structure of the sensor and connection to the ECM is the same as in the
intake air temp. circuit malfunction shown on page DI-24.
If the ECM detects the DTC P0115, it operates the fail-safe function in which the engine coolant temp. is
assumed to be 80°C (176°F).
DTC No.DTC Detection ConditionTrouble Area
P0115Open or short in engine coolant temp. sensor circuit

Open or short in engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
HINT:
After confirming DTC P0115, use the OBD II scan tool or TOYOTA hand-held tester to confirm the engine
coolant temperature from the CURRENT DATA.
Temperature DisplayedMalfunction
-40°C (-40°F)Open circuit
140°C (284°F) or moreShort circuit
WIRING DIAGRAM
DI1E6-08

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).