1996 TOYOTA TERCEL ECM

- 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.

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

- DIAGNOSTICSENGINE
DI-15
1996 TERCEL (RM440U)
Manufacturer Controlled:
DTC No.
(See Page)Detection ItemTrouble AreaMIL*Memory
P1300
(DI-84)Igniter Circuit Malfunction
Open or short in IGF or IGT circuit from igniter to ECM
Igniter
ECM

P1335
(DI-89)Crankshaft Position Sensor
Circuit Malfunction
(during engine running)Open or short in crankshaft position sensor circuit
Crankshaft position sensor
ECM
-
P1600
(DI-92)ECM BATT MalfunctionOpen in back up power source circuit
ECM
P1780
(DI-94)Park/Neutral Position Switch
MalfunctionShort in park/neutral position switch circuit
Park/neutral position switch
ECM

*:-


MIL does not light up



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

DI-18
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)Symbols (Terminals No.)
Wiring ColorConditionSTD Voltage (V)
RSC (E7-1) - E1 (E7-24)L-R - BRIG switch ON
Disconnect ºE7º of ECM connector9 - 14
RSO (E7-14) - E1(E7-24)L - BRIG switch ON
Disconnect ºE7º of ECM connector9 - 14
OX1 (E7-10) - E1 (E7-24)B - BRMaintain engine speed at 2,500 rpm for 2 minutes. after
warming upPulse generation
OX2 (E7-23) - E1 (E7-24)W - BRMaintain engine speed at 2,500 rpm for 2 minutes. after
warming upPulse generation
HT1 (E6 6) E03 (E7 26)WL BRIdlingBelow 3.0HT1 (E6-6) - E03 (E7-26)W-L - BRIG switch ON9 - 14
HT2 (E6 5) E03 (E7 26)WR BRIdlingBelow 3.0HT2 (E6-5) - E03 (E7-26)W-R - BRIG switch ON9 - 14
KNK (E7-8) - E1 (E7-24)B - BRIdlingPulse generation
(See page DI-57)
NSW (E7 2) E1 (E7 24)(M/T)
IG switch ON
Other shift position in ºPº or ºNº position9 - 14
NSW (E7-2) - E1 (E7-24)(M/T)IG switch ON
Shift position in ºPº or ºNº position0 - 3.0
NSW (E7 2) E1 (E7 24)(A/T)
IG switch ON
Other shift position in ºPº or ºNº position9 - 14
NSW (E7-2) - E1 (E7-24)(A/T)IG switch ON
Shift position in ºPº or Nº position0 - 3.0
SPD (E6-13) - E1 (E7-24)Y - BRIG switch ON
Rotate driving wheel slowlyPulse generation
(See page DI-76)
TE1 (E6-8) - E1 (E7-24)G - BRIG switch ON9 - 14
W (E6 10) E1 (E7 24)GR L BRIdling9 - 14W (E6-10) - E1 (E7-24)GR-L - BRIG switch ONBelow 3.0
AC1 (E6 12) E1 (E7 24)LG B BRIdling, A/C switch ONBelow 2.0AC1 (E6-12) - E1 (E7-24)LG-B - BRIdling, A/C switch OFF9 - 14
ACT (E6 14) E1 (E7 24)LBRIdling, A/C switch ON9 - 14ACT (E6-14) - E1 (E7-24)L - BRIdling, A/C switch OFFBelow 2.0
ODSW (E6 3) E1 (E7 24)RW BRIG switch ON, O/D main switch pushed out9 - 14ODSW (E6-3) - E1 (E7-24)R-W - BRIG switch ON, O/D main switch pushed in0 - 3.0
ODT (E6 11) E1 (E7 24)RBRIG switch ON, O/D main switch pushed out9 - 14ODT (E6-11) - E1 (E7-24)R - BRIG switch ON, O/D main switch pushed in0 - 3.0

DI4LI-02
- DIAGNOSTICSENGINE
DI-19
1996 TERCEL (RM440U)
PROBLEM SYMPTOMS TABLE
SymptomSuspect AreaSee page
Does not start (Engine does not crank)1. Starter and starter relayST-13
ST-31
Does not start (No combustion)1. ECM power source circuit
2. Fuel pump control circuitDI-97
DI-100
Does not start (No complete combustion)1. Fuel pump control circuitDI-100
Difficult to start (Engine cranks normally)
1. Starter signal circuit
2. Fuel pump control circuit
3. CompressionDI-90
DI-100
EM-3
Difficult to start (Cold engine)1. Starter signal circuit
2. Fuel pump control circuitDI-90
DI-100
Difficult to start (Hot engine)1. Starter signal circuit
2. Fuel pump control circuitDI-90
DI-100
Poor idling (High engine idle speed)1. A/C signal circuit
2. ECM power source circuitAC-66
DI-97
Poor idling (Low engine idle speed)1. A/C signal circuit
2. Fuel pump control circuitAC-66
DI-100
Poor idling (Rough idling)1. Compression
2. Fuel pump control circuitEM-3
DI-100
Poor idling (Hunting)1. ECM power source circuit
2. Fuel pump control circuitDI-97
DI-100
Poor driveability (Hesitation/Poor acceleration)
1. Fuel pump control circuit
2. A/T faulty (A132L)
A/T faulty (A242L)
3. A/C cut control circuitDI-100
AX-10
AX-13
DI-106
Poor driveability (Surging)1. Fuel pump control circuitDI-100
Engine stall (Soon after starting)1. Fuel pump control circuitDI-100
Engine stall (During A/C operation)1. A/C signal circuit
2. Engine control module (ECM)AC-66
IN-26

DI1E3-06
P01242
750
450
100 (3.96)
3.6
1.2
(840) 2.4
150
60 20
(112)kPa mmHg
Manifold Absolute Pressure
Output Voltage
V DI-20
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
CIRCUIT INSPECTION
DTC P0105 Manifold Absolute Pressure/Barometric
Pressure Circuit Malfunction
CIRCUIT DESCRIPTION
By a built-in sensor unit, the manifold absolute pressure sensor
detects the intake manifold pressure as a voltage. The ECM
then determines the basic injection duration and basic injection
advance angle based on this voltage. Since the manifold abso-
lute pressure sensor does not use the atmospheric pressure as
a criterion, but senses the absolute pressure inside the intake
manifold (the pressure in proportion to the present absolute
vacuum 0), it is not influenced by fluctuations in the atmospheric
pressure due to high altitude and other factors. This permits it
to control the air-fuel ratio at the proper lever under all condi-
tions.
DTC No.DTC Detection ConditionTrouble Area
P0105Open or short manifold absolute pressure sensor circuit

Open or short in manifold absolute pressure sensor circuit

Manifold absolute pressure sensor

ECM
If the ECM detects DTC P0105, it operates the fail-safe function, keeping the ignition timing and injection
volume constant and making it possible to drive the vehicle.
HINT:
After confirming DTC P0105, use the OBDII scan tool or TOYOTA hand-held tester to confirm the manifold
absolute pressure from the CURRENT DATA.
Manifold absolute pressureTrouble Area
0 kPaPIM circuit short
130 kPa or more
VC circuit open or short
PIM circuit open
E2 circuit open